diff --git a/models/Expense.js b/models/Expense.js
index 39c28cb..dde44ab 100644
--- a/models/Expense.js
+++ b/models/Expense.js
@@ -72,6 +72,15 @@ const expenseSchema = new mongoose.Schema({
   isPrivate: {
     type: Boolean,
     default: false
+  },
+  status: {
+    type: String,
+    enum: ['draft', 'pending_approval', 'approved', 'rejected'],
+    default: 'approved' // Default to approved for backward compatibility
+  },
+  approvalWorkflow: {
+    type: mongoose.Schema.Types.ObjectId,
+    ref: 'ApprovalWorkflow'
   }
 }, {
   timestamps: true
diff --git a/public/expensetracker.css b/public/expensetracker.css
index 8818a40..c8742c0 100644
--- a/public/expensetracker.css
+++ b/public/expensetracker.css
@@ -5912,3 +5912,397 @@ button {
   font-size: 2rem;
   color: var(--accent-primary);
 }
+
+/* Settings Section Styles */
+.settings-section {
+  padding: 2rem 0;
+  background: var(--bg-secondary);
+}
+
+.settings-container {
+  max-width: 1200px;
+  margin: 0 auto;
+  padding: 0 2rem;
+}
+
+.settings-tabs {
+  display: flex;
+  gap: 1rem;
+  margin-bottom: 2rem;
+  border-bottom: 1px solid var(--bg-glass);
+  padding-bottom: 1rem;
+}
+
+.settings-tab {
+  background: none;
+  border: none;
+  color: var(--text-secondary);
+  padding: 0.75rem 1.5rem;
+  border-radius: 8px;
+  cursor: pointer;
+  transition: all 0.3s ease;
+  font-size: 1rem;
+  font-weight: 500;
+}
+
+.settings-tab:hover {
+  background: var(--bg-glass);
+  color: var(--text-primary);
+}
+
+.settings-tab.active {
+  background: var(--primary-gradient);
+  color: white;
+}
+
+.settings-content {
+  display: none;
+}
+
+.settings-content.active {
+  display: block;
+}
+
+.settings-card {
+  background: var(--bg-tertiary);
+  border-radius: 12px;
+  padding: 2rem;
+  margin-bottom: 2rem;
+  backdrop-filter: blur(10px);
+  border: 1px solid var(--bg-glass);
+  box-shadow: var(--shadow-card);
+}
+
+.settings-card h4 {
+  color: var(--text-primary);
+  margin-bottom: 1.5rem;
+  font-size: 1.25rem;
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+}
+
+.settings-card h4 i {
+  color: var(--accent-primary);
+}
+
+/* Workspace Settings */
+.workspace-info {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: 2rem;
+  margin-bottom: 2rem;
+}
+
+.workspace-info label {
+  display: block;
+  color: var(--text-secondary);
+  margin-bottom: 0.5rem;
+  font-weight: 500;
+}
+
+.workspace-info span,
+.workspace-info select {
+  color: var(--text-primary);
+  font-weight: 600;
+}
+
+.workspace-actions {
+  margin-top: 1rem;
+}
+
+.members-list {
+  margin-bottom: 1.5rem;
+}
+
+.member-item {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: 1rem;
+  background: var(--bg-glass);
+  border-radius: 8px;
+  margin-bottom: 0.5rem;
+}
+
+.member-info {
+  display: flex;
+  align-items: center;
+  gap: 1rem;
+}
+
+.member-avatar {
+  width: 40px;
+  height: 40px;
+  border-radius: 50%;
+  background: var(--primary-gradient);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  color: white;
+  font-weight: bold;
+}
+
+.member-details h5 {
+  color: var(--text-primary);
+  margin-bottom: 0.25rem;
+}
+
+.member-role {
+  color: var(--text-secondary);
+  font-size: 0.875rem;
+}
+
+.member-actions {
+  display: flex;
+  gap: 0.5rem;
+}
+
+.btn-role {
+  background: var(--bg-glass);
+  border: 1px solid var(--accent-primary);
+  color: var(--accent-primary);
+  padding: 0.25rem 0.75rem;
+  border-radius: 4px;
+  cursor: pointer;
+  font-size: 0.875rem;
+}
+
+.btn-role:hover {
+  background: var(--accent-primary);
+  color: white;
+}
+
+.btn-remove {
+  background: var(--error);
+  color: white;
+  border: none;
+  padding: 0.25rem 0.75rem;
+  border-radius: 4px;
+  cursor: pointer;
+  font-size: 0.875rem;
+}
+
+.btn-remove:hover {
+  opacity: 0.8;
+}
+
+/* Approvals Settings */
+.approval-config {
+  margin-bottom: 2rem;
+}
+
+.approval-config .form-control {
+  margin-bottom: 1rem;
+}
+
+.approval-config small {
+  color: var(--text-secondary);
+  font-size: 0.875rem;
+}
+
+.approvals-list {
+  max-height: 400px;
+  overflow-y: auto;
+}
+
+.approval-item {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: 1rem;
+  background: var(--bg-glass);
+  border-radius: 8px;
+  margin-bottom: 0.5rem;
+}
+
+.approval-info {
+  flex: 1;
+}
+
+.approval-info h5 {
+  color: var(--text-primary);
+  margin-bottom: 0.25rem;
+}
+
+.approval-details {
+  color: var(--text-secondary);
+  font-size: 0.875rem;
+}
+
+.approval-status {
+  padding: 0.25rem 0.75rem;
+  border-radius: 20px;
+  font-size: 0.75rem;
+  font-weight: 600;
+  text-transform: uppercase;
+}
+
+.status-pending {
+  background: var(--warning);
+  color: #333;
+}
+
+.status-approved {
+  background: var(--success);
+  color: white;
+}
+
+.status-rejected {
+  background: var(--error);
+  color: white;
+}
+
+.approval-actions {
+  display: flex;
+  gap: 0.5rem;
+}
+
+.btn-approve {
+  background: var(--success);
+  color: white;
+  border: none;
+  padding: 0.5rem 1rem;
+  border-radius: 4px;
+  cursor: pointer;
+  font-size: 0.875rem;
+}
+
+.btn-reject {
+  background: var(--error);
+  color: white;
+  border: none;
+  padding: 0.5rem 1rem;
+  border-radius: 4px;
+  cursor: pointer;
+  font-size: 0.875rem;
+}
+
+/* Profile Settings */
+.profile-form .form-control {
+  margin-bottom: 1rem;
+}
+
+.profile-form input[readonly] {
+  background: var(--bg-glass);
+  cursor: not-allowed;
+}
+
+/* Responsive Design */
+@media (max-width: 768px) {
+  .settings-container {
+    padding: 0 1rem;
+  }
+
+  .workspace-info {
+    grid-template-columns: 1fr;
+    gap: 1rem;
+  }
+
+  .settings-tabs {
+    flex-wrap: wrap;
+  }
+
+  .settings-tab {
+    flex: 1;
+    min-width: 120px;
+  }
+
+  .member-item {
+    flex-direction: column;
+    align-items: flex-start;
+    gap: 1rem;
+  }
+
+  .member-actions {
+    width: 100%;
+    justify-content: flex-end;
+  }
+
+  .approval-item {
+    flex-direction: column;
+    align-items: flex-start;
+    gap: 1rem;
+  }
+
+  .approval-actions {
+    width: 100%;
+    justify-content: flex-end;
+  }
+}
+
+/* Approval Status Badges */
+.approval-badge {
+  padding: 0.25rem 0.5rem;
+  border-radius: 12px;
+  font-size: 0.75rem;
+  font-weight: 600;
+  text-transform: uppercase;
+  display: inline-block;
+  margin-left: 0.5rem;
+}
+
+.status-approved {
+  background: var(--success);
+  color: white;
+}
+
+.status-pending {
+  background: var(--warning);
+  color: #333;
+}
+
+.status-rejected {
+  background: var(--error);
+  color: white;
+}
+
+.transaction-meta {
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+}
+
+/* Notification Styles */
+.notification {
+  position: fixed;
+  top: 20px;
+  right: 20px;
+  background: var(--bg-tertiary);
+  color: var(--text-primary);
+  padding: 1rem 1.5rem;
+  border-radius: 8px;
+  box-shadow: var(--shadow-card);
+  border-left: 4px solid var(--accent-primary);
+  z-index: 10000;
+  transform: translateX(100%);
+  transition: transform 0.3s ease;
+  max-width: 400px;
+}
+
+.notification.show {
+  transform: translateX(0);
+}
+
+.notification-success {
+  border-left-color: var(--success);
+}
+
+.notification-error {
+  border-left-color: var(--error);
+}
+
+.notification-info {
+  border-left-color: var(--accent-primary);
+}
+
+.notification i {
+  margin-right: 0.5rem;
+}
+
+.no-approvals {
+  text-align: center;
+  color: var(--text-secondary);
+  padding: 2rem;
+  font-style: italic;
+}
diff --git a/public/index.html b/public/index.html
index 312b3ff..a0dc5ac 100644
--- a/public/index.html
+++ b/public/index.html
@@ -890,91 +890,101 @@ <h3><i class="fas fa-chart-bar"></i> Financial Analytics & Forecasting</h3>
     </div>
 
     <!-- Settings Section -->
-    <section id="settings" class="settings-section" style="display: none; padding-top: 100px;">
-      <div class="container">
-        <div class="section-header">
-          <h3><i class="fas fa-cog"></i> Settings</h3>
+    <section id="settings" class="settings-section">
+      <div class="section-header">
+        <h3><i class="fas fa-cog"></i> Settings</h3>
+      </div>
+
+      <div class="settings-container">
+        <!-- Workspace Settings Tab -->
+        <div class="settings-tabs">
+          <button class="settings-tab active" onclick="switchSettingsTab('workspace')">Workspace</button>
+          <button class="settings-tab" onclick="switchSettingsTab('approvals')">Approvals</button>
+          <button class="settings-tab" onclick="switchSettingsTab('profile')">Profile</button>
         </div>
 
         <!-- Workspace Settings -->
-        <div id="workspace-settings" class="settings-card" style="display: none;">
-          <div class="settings-header">
+        <div id="workspace-settings" class="settings-content active">
+          <div class="settings-card">
             <h4><i class="fas fa-users"></i> Workspace Management</h4>
-            <span class="settings-subtitle">Manage members, roles, and permissions</span>
-          </div>
-
-          <div class="workspace-info">
-            <div class="workspace-details">
-              <h5 id="current-workspace-name">Workspace Name</h5>
-              <p id="current-workspace-desc">Workspace description</p>
-              <div class="workspace-stats">
-                <span id="member-count">0 members</span>
-                <span id="your-role">Your role: member</span>
+            <div class="workspace-info">
+              <div class="current-workspace">
+                <label>Current Workspace:</label>
+                <span id="current-workspace-name">Personal</span>
+              </div>
+              <div class="workspace-selector">
+                <label for="workspace-select">Switch Workspace:</label>
+                <select id="workspace-select" onchange="switchWorkspace()">
+                  <option value="personal">Personal</option>
+                </select>
               </div>
             </div>
-          </div>
 
-          <!-- Members Management -->
-          <div class="members-section">
-            <div class="section-header-small">
-              <h5>Members</h5>
-              <button class="btn-secondary" onclick="openInviteModal()" id="invite-btn" style="display: none;">
-                <i class="fas fa-user-plus"></i> Invite Member
+            <div class="workspace-actions">
+              <button class="btn-secondary" onclick="openCreateWorkspaceModal()">
+                <i class="fas fa-plus"></i> Create New Workspace
               </button>
             </div>
+          </div>
 
+          <div class="settings-card">
+            <h4><i class="fas fa-user-friends"></i> Members</h4>
             <div id="members-list" class="members-list">
               <!-- Members will be loaded here -->
             </div>
+            <button class="btn-secondary" onclick="openInviteModal()">
+              <i class="fas fa-user-plus"></i> Invite Member
+            </button>
           </div>
+        </div>
 
-          <!-- Role Permissions Info -->
-          <div class="permissions-info">
-            <h5>Role Permissions</h5>
-            <div class="permissions-grid">
-              <div class="permission-item">
-                <strong>Owner:</strong> Full access to all features, manage members, delete workspace
-              </div>
-              <div class="permission-item">
-                <strong>Admin:</strong> Manage members and their roles, access all workspace data
-              </div>
-              <div class="permission-item">
-                <strong>Manager:</strong> Manage budgets, approve expenses, access all data
-              </div>
-              <div class="permission-item">
-                <strong>Member:</strong> Add and edit expenses, view all reports
-              </div>
-              <div class="permission-item">
-                <strong>Viewer:</strong> View expenses and reports, cannot make changes
+        <!-- Approvals Settings -->
+        <div id="approvals-settings" class="settings-content">
+          <div class="settings-card">
+            <h4><i class="fas fa-check-circle"></i> Expense Approvals</h4>
+            <div class="approval-config">
+              <div class="form-control">
+                <label for="approval-required">Require Approval for Expenses Over:</label>
+                <input type="number" id="approval-required" placeholder="10000" min="0" step="100">
+                <small>Set to 0 to disable approval workflow</small>
               </div>
+              <button class="btn-submit" onclick="saveApprovalSettings()">
+                <i class="fas fa-save"></i> Save Settings
+              </button>
             </div>
           </div>
-        </div>
 
-        <!-- Personal Settings -->
-        <div class="settings-card">
-          <div class="settings-header">
-            <h4><i class="fas fa-user"></i> Personal Settings</h4>
-            <span class="settings-subtitle">Manage your account preferences</span>
+          <div class="settings-card">
+            <h4><i class="fas fa-clock"></i> Pending Approvals</h4>
+            <div id="pending-approvals" class="approvals-list">
+              <!-- Pending approvals will be loaded here -->
+            </div>
           </div>
 
-          <div class="settings-content">
-            <div class="setting-item">
-              <label for="default-currency">Default Currency</label>
-              <select id="default-currency" onchange="updateDefaultCurrency()">
-                <option value="INR">INR (₹)</option>
-                <option value="USD">USD ($)</option>
-                <option value="EUR">EUR (€)</option>
-                <option value="GBP">GBP (£)</option>
-              </select>
+          <div class="settings-card">
+            <h4><i class="fas fa-history"></i> Approval History</h4>
+            <div id="approval-history" class="approvals-list">
+              <!-- Approval history will be loaded here -->
             </div>
+          </div>
+        </div>
 
-            <div class="setting-item">
-              <label for="theme-toggle">Theme</label>
-              <select id="theme-toggle">
-                <option value="dark">Dark</option>
-                <option value="light">Light</option>
-              </select>
+        <!-- Profile Settings -->
+        <div id="profile-settings" class="settings-content">
+          <div class="settings-card">
+            <h4><i class="fas fa-user"></i> Profile Information</h4>
+            <div class="profile-form">
+              <div class="form-control">
+                <label for="profile-name">Full Name:</label>
+                <input type="text" id="profile-name" placeholder="Your full name">
+              </div>
+              <div class="form-control">
+                <label for="profile-email">Email:</label>
+                <input type="email" id="profile-email" placeholder="your.email@example.com" readonly>
+              </div>
+              <button class="btn-submit" onclick="updateProfile()">
+                <i class="fas fa-save"></i> Update Profile
+              </button>
             </div>
           </div>
         </div>
@@ -1713,6 +1723,7 @@ <h3>Install ExpenseFlow</h3>
   <script src="auth.js"></script>
   <script src="trackerscript.js"></script>
   <script src="analytics-dashboard.js"></script>
+  <script src="workspace-feature.js"></script>
 
 
 </body>
diff --git a/public/trackerscript.js b/public/trackerscript.js
index 647ddc8..ee4b43f 100644
--- a/public/trackerscript.js
+++ b/public/trackerscript.js
@@ -115,7 +115,8 @@ document.addEventListener("DOMContentLoaded", () => {
         amount: expense.type === 'expense' ? -expense.amount : expense.amount,
         category: expense.category,
         type: expense.type,
-        date: expense.date
+        date: expense.date,
+        approvalStatus: expense.approvalStatus || 'approved' // Default to approved for backward compatibility
       }));
     } catch (error) {
       console.error('Error fetching expenses:', error);
@@ -552,6 +553,14 @@ document.addEventListener("DOMContentLoaded", () => {
     const formattedDate = date.toLocaleDateString('en-IN');
     const categoryInfo = categories[transaction.category] || categories.other;
 
+    // Determine approval status
+    let statusBadge = '';
+    if (transaction.approvalStatus) {
+      const status = transaction.approvalStatus.toLowerCase();
+      const statusText = transaction.approvalStatus.charAt(0).toUpperCase() + transaction.approvalStatus.slice(1);
+      statusBadge = `<span class="approval-badge status-${status}">${statusText}</span>`;
+    }
+
     item.innerHTML = `
       <div class="transaction-content">
         <div class="transaction-main">
@@ -562,7 +571,10 @@ document.addEventListener("DOMContentLoaded", () => {
           <span class="transaction-category" style="background-color: ${categoryInfo.color}20; color: ${categoryInfo.color};">
             ${categoryInfo.name}
           </span>
-          <div class="transaction-date">${formattedDate}</div>
+          <div class="transaction-meta">
+            <div class="transaction-date">${formattedDate}</div>
+            ${statusBadge}
+          </div>
         </div>
       </div>
       <button class="delete-btn" onclick="removeTransaction('${transaction.id}')">
diff --git a/public/workspace-feature.js b/public/workspace-feature.js
new file mode 100644
index 0000000..4176cfc
--- /dev/null
+++ b/public/workspace-feature.js
@@ -0,0 +1,515 @@
+// Workspace and Settings Management
+let currentWorkspace = null;
+let currentUser = null;
+
+// Initialize workspace features
+document.addEventListener('DOMContentLoaded', function() {
+  initializeWorkspaceFeatures();
+  loadCurrentUser();
+  loadWorkspaceData();
+});
+
+function initializeWorkspaceFeatures() {
+  // Settings tab switching
+  window.switchSettingsTab = switchSettingsTab;
+
+  // Workspace functions
+  window.switchWorkspace = switchWorkspace;
+  window.openCreateWorkspaceModal = openCreateWorkspaceModal;
+  window.openInviteModal = openInviteModal;
+
+  // Approval functions
+  window.saveApprovalSettings = saveApprovalSettings;
+
+  // Profile functions
+  window.updateProfile = updateProfile;
+}
+
+async function loadCurrentUser() {
+  try {
+    const token = localStorage.getItem('authToken');
+    if (!token) return;
+
+    const response = await fetch('/api/auth/me', {
+      headers: {
+        'Authorization': `Bearer ${token}`
+      }
+    });
+
+    const data = await response.json();
+    if (data.success) {
+      currentUser = data.user;
+      updateUserDisplay();
+    }
+  } catch (error) {
+    console.error('Error loading user:', error);
+  }
+}
+
+function updateUserDisplay() {
+  if (!currentUser) return;
+
+  const usernameEl = document.getElementById('navUsername');
+  if (usernameEl) {
+    usernameEl.textContent = currentUser.name || currentUser.email;
+  }
+
+  // Update profile settings
+  const profileName = document.getElementById('profile-name');
+  const profileEmail = document.getElementById('profile-email');
+
+  if (profileName) profileName.value = currentUser.name || '';
+  if (profileEmail) profileEmail.value = currentUser.email || '';
+}
+
+async function loadWorkspaceData() {
+  try {
+    const token = localStorage.getItem('authToken');
+    if (!token) return;
+
+    // Load current workspace
+    const workspaceResponse = await fetch('/api/workspaces/current', {
+      headers: {
+        'Authorization': `Bearer ${token}`
+      }
+    });
+
+    const workspaceData = await workspaceResponse.json();
+    if (workspaceData.success) {
+      currentWorkspace = workspaceData.workspace;
+      updateWorkspaceDisplay();
+      loadMembers();
+    }
+
+    // Load approval settings
+    loadApprovalSettings();
+
+    // Load pending approvals
+    loadPendingApprovals();
+
+    // Load approval history
+    loadApprovalHistory();
+
+  } catch (error) {
+    console.error('Error loading workspace data:', error);
+  }
+}
+
+function updateWorkspaceDisplay() {
+  if (!currentWorkspace) return;
+
+  const workspaceNameEl = document.getElementById('current-workspace-name');
+  if (workspaceNameEl) {
+    workspaceNameEl.textContent = currentWorkspace.name;
+  }
+}
+
+async function loadMembers() {
+  try {
+    const token = localStorage.getItem('authToken');
+    if (!token || !currentWorkspace) return;
+
+    const response = await fetch(`/api/workspaces/${currentWorkspace._id}/members`, {
+      headers: {
+        'Authorization': `Bearer ${token}`
+      }
+    });
+
+    const data = await response.json();
+    if (data.success) {
+      renderMembersList(data.members);
+    }
+  } catch (error) {
+    console.error('Error loading members:', error);
+  }
+}
+
+function renderMembersList(members) {
+  const membersList = document.getElementById('members-list');
+  if (!membersList) return;
+
+  membersList.innerHTML = '';
+
+  members.forEach(member => {
+    const memberItem = document.createElement('div');
+    memberItem.className = 'member-item';
+
+    memberItem.innerHTML = `
+      <div class="member-info">
+        <div class="member-avatar">
+          ${member.name ? member.name.charAt(0).toUpperCase() : member.email.charAt(0).toUpperCase()}
+        </div>
+        <div class="member-details">
+          <h5>${member.name || member.email}</h5>
+          <span class="member-role">${member.role}</span>
+        </div>
+      </div>
+      <div class="member-actions">
+        ${canManageMember(member) ? `
+          <select class="btn-role" onchange="changeMemberRole('${member._id}', this.value)">
+            <option value="viewer" ${member.role === 'viewer' ? 'selected' : ''}>Viewer</option>
+            <option value="member" ${member.role === 'member' ? 'selected' : ''}>Member</option>
+            <option value="manager" ${member.role === 'manager' ? 'selected' : ''}>Manager</option>
+            <option value="admin" ${member.role === 'admin' ? 'selected' : ''}>Admin</option>
+          </select>
+          ${member._id !== currentUser._id ? `
+            <button class="btn-remove" onclick="removeMember('${member._id}')">
+              <i class="fas fa-user-minus"></i>
+            </button>
+          ` : ''}
+        ` : ''}
+      </div>
+    `;
+
+    membersList.appendChild(memberItem);
+  });
+}
+
+function canManageMember(member) {
+  if (!currentUser || !currentWorkspace) return false;
+
+  // Owner can manage everyone
+  if (currentWorkspace.owner.toString() === currentUser._id.toString()) {
+    return true;
+  }
+
+  // Admins can manage members and viewers
+  if (currentUser.role === 'admin' && ['member', 'viewer'].includes(member.role)) {
+    return true;
+  }
+
+  return false;
+}
+
+async function changeMemberRole(memberId, newRole) {
+  try {
+    const token = localStorage.getItem('authToken');
+    if (!token || !currentWorkspace) return;
+
+    const response = await fetch(`/api/workspaces/${currentWorkspace._id}/members/${memberId}`, {
+      method: 'PUT',
+      headers: {
+        'Authorization': `Bearer ${token}`,
+        'Content-Type': 'application/json'
+      },
+      body: JSON.stringify({ role: newRole })
+    });
+
+    const data = await response.json();
+    if (data.success) {
+      loadMembers(); // Reload members list
+      showNotification('Member role updated successfully', 'success');
+    } else {
+      showNotification(data.message || 'Failed to update member role', 'error');
+    }
+  } catch (error) {
+    console.error('Error updating member role:', error);
+    showNotification('Error updating member role', 'error');
+  }
+}
+
+async function removeMember(memberId) {
+  if (!confirm('Are you sure you want to remove this member from the workspace?')) {
+    return;
+  }
+
+  try {
+    const token = localStorage.getItem('authToken');
+    if (!token || !currentWorkspace) return;
+
+    const response = await fetch(`/api/workspaces/${currentWorkspace._id}/members/${memberId}`, {
+      method: 'DELETE',
+      headers: {
+        'Authorization': `Bearer ${token}`
+      }
+    });
+
+    const data = await response.json();
+    if (data.success) {
+      loadMembers(); // Reload members list
+      showNotification('Member removed successfully', 'success');
+    } else {
+      showNotification(data.message || 'Failed to remove member', 'error');
+    }
+  } catch (error) {
+    console.error('Error removing member:', error);
+    showNotification('Error removing member', 'error');
+  }
+}
+
+function switchSettingsTab(tabName) {
+  // Hide all settings content
+  const contents = document.querySelectorAll('.settings-content');
+  contents.forEach(content => content.classList.remove('active'));
+
+  // Remove active class from all tabs
+  const tabs = document.querySelectorAll('.settings-tab');
+  tabs.forEach(tab => tab.classList.remove('active'));
+
+  // Show selected content and activate tab
+  const selectedContent = document.getElementById(`${tabName}-settings`);
+  const selectedTab = Array.from(tabs).find(tab => tab.textContent.toLowerCase() === tabName);
+
+  if (selectedContent) selectedContent.classList.add('active');
+  if (selectedTab) selectedTab.classList.add('active');
+}
+
+function switchWorkspace() {
+  const select = document.getElementById('workspace-select');
+  if (!select) return;
+
+  const workspaceId = select.value;
+  // TODO: Implement workspace switching
+  showNotification('Workspace switching not yet implemented', 'info');
+}
+
+function openCreateWorkspaceModal() {
+  // TODO: Implement create workspace modal
+  showNotification('Create workspace feature not yet implemented', 'info');
+}
+
+function openInviteModal() {
+  // TODO: Implement invite modal
+  showNotification('Invite member feature not yet implemented', 'info');
+}
+
+// Approval Settings Functions
+async function loadApprovalSettings() {
+  try {
+    const token = localStorage.getItem('authToken');
+    if (!token || !currentWorkspace) return;
+
+    const response = await fetch(`/api/workspaces/${currentWorkspace._id}/settings`, {
+      headers: {
+        'Authorization': `Bearer ${token}`
+      }
+    });
+
+    const data = await response.json();
+    if (data.success) {
+      const approvalRequired = document.getElementById('approval-required');
+      if (approvalRequired && data.settings.approvalThreshold) {
+        approvalRequired.value = data.settings.approvalThreshold;
+      }
+    }
+  } catch (error) {
+    console.error('Error loading approval settings:', error);
+  }
+}
+
+async function saveApprovalSettings() {
+  try {
+    const token = localStorage.getItem('authToken');
+    if (!token || !currentWorkspace) return;
+
+    const approvalRequired = document.getElementById('approval-required');
+    if (!approvalRequired) return;
+
+    const threshold = parseFloat(approvalRequired.value) || 0;
+
+    const response = await fetch(`/api/workspaces/${currentWorkspace._id}/settings`, {
+      method: 'PUT',
+      headers: {
+        'Authorization': `Bearer ${token}`,
+        'Content-Type': 'application/json'
+      },
+      body: JSON.stringify({
+        approvalThreshold: threshold
+      })
+    });
+
+    const data = await response.json();
+    if (data.success) {
+      showNotification('Approval settings saved successfully', 'success');
+    } else {
+      showNotification(data.message || 'Failed to save approval settings', 'error');
+    }
+  } catch (error) {
+    console.error('Error saving approval settings:', error);
+    showNotification('Error saving approval settings', 'error');
+  }
+}
+
+async function loadPendingApprovals() {
+  try {
+    const token = localStorage.getItem('authToken');
+    if (!token) return;
+
+    const response = await fetch('/api/approvals/pending', {
+      headers: {
+        'Authorization': `Bearer ${token}`
+      }
+    });
+
+    const data = await response.json();
+    if (data.success) {
+      renderApprovalsList('pending-approvals', data.approvals, true);
+    }
+  } catch (error) {
+    console.error('Error loading pending approvals:', error);
+  }
+}
+
+async function loadApprovalHistory() {
+  try {
+    const token = localStorage.getItem('authToken');
+    if (!token) return;
+
+    const response = await fetch('/api/approvals/history', {
+      headers: {
+        'Authorization': `Bearer ${token}`
+      }
+    });
+
+    const data = await response.json();
+    if (data.success) {
+      renderApprovalsList('approval-history', data.approvals, false);
+    }
+  } catch (error) {
+    console.error('Error loading approval history:', error);
+  }
+}
+
+function renderApprovalsList(containerId, approvals, showActions = false) {
+  const container = document.getElementById(containerId);
+  if (!container) return;
+
+  container.innerHTML = '';
+
+  if (approvals.length === 0) {
+    container.innerHTML = '<p class="no-approvals">No approvals found</p>';
+    return;
+  }
+
+  approvals.forEach(approval => {
+    const approvalItem = document.createElement('div');
+    approvalItem.className = 'approval-item';
+
+    const statusClass = `status-${approval.status.toLowerCase()}`;
+
+    approvalItem.innerHTML = `
+      <div class="approval-info">
+        <h5>${approval.expense.description}</h5>
+        <div class="approval-details">
+          Amount: ₹${approval.expense.amount} |
+          Submitted by: ${approval.submittedBy.name || approval.submittedBy.email} |
+          Date: ${new Date(approval.createdAt).toLocaleDateString()}
+        </div>
+      </div>
+      <div class="approval-status ${statusClass}">${approval.status}</div>
+      ${showActions ? `
+        <div class="approval-actions">
+          <button class="btn-approve" onclick="approveExpense('${approval._id}')">
+            <i class="fas fa-check"></i> Approve
+          </button>
+          <button class="btn-reject" onclick="rejectExpense('${approval._id}')">
+            <i class="fas fa-times"></i> Reject
+          </button>
+        </div>
+      ` : ''}
+    `;
+
+    container.appendChild(approvalItem);
+  });
+}
+
+async function approveExpense(approvalId) {
+  await processApproval(approvalId, 'approved');
+}
+
+async function rejectExpense(approvalId) {
+  await processApproval(approvalId, 'rejected');
+}
+
+async function processApproval(approvalId, status) {
+  try {
+    const token = localStorage.getItem('authToken');
+    if (!token) return;
+
+    const response = await fetch(`/api/approvals/${approvalId}`, {
+      method: 'PUT',
+      headers: {
+        'Authorization': `Bearer ${token}`,
+        'Content-Type': 'application/json'
+      },
+      body: JSON.stringify({ status })
+    });
+
+    const data = await response.json();
+    if (data.success) {
+      showNotification(`Expense ${status} successfully`, 'success');
+      loadPendingApprovals();
+      loadApprovalHistory();
+      // Refresh expense list to show updated status
+      if (typeof loadExpenses === 'function') {
+        loadExpenses();
+      }
+    } else {
+      showNotification(data.message || `Failed to ${status} expense`, 'error');
+    }
+  } catch (error) {
+    console.error(`Error ${status} expense:`, error);
+    showNotification(`Error ${status} expense`, 'error');
+  }
+}
+
+// Profile Functions
+async function updateProfile() {
+  try {
+    const token = localStorage.getItem('authToken');
+    if (!token) return;
+
+    const nameInput = document.getElementById('profile-name');
+    if (!nameInput) return;
+
+    const newName = nameInput.value.trim();
+    if (!newName) {
+      showNotification('Name cannot be empty', 'error');
+      return;
+    }
+
+    const response = await fetch('/api/auth/profile', {
+      method: 'PUT',
+      headers: {
+        'Authorization': `Bearer ${token}`,
+        'Content-Type': 'application/json'
+      },
+      body: JSON.stringify({ name: newName })
+    });
+
+    const data = await response.json();
+    if (data.success) {
+      currentUser.name = newName;
+      updateUserDisplay();
+      showNotification('Profile updated successfully', 'success');
+    } else {
+      showNotification(data.message || 'Failed to update profile', 'error');
+    }
+  } catch (error) {
+    console.error('Error updating profile:', error);
+    showNotification('Error updating profile', 'error');
+  }
+}
+
+// Utility function for notifications
+function showNotification(message, type = 'info') {
+  // Create notification element
+  const notification = document.createElement('div');
+  notification.className = `notification notification-${type}`;
+  notification.innerHTML = `
+    <i class="fas ${type === 'success' ? 'fa-check-circle' : type === 'error' ? 'fa-exclamation-circle' : 'fa-info-circle'}"></i>
+    <span>${message}</span>
+  `;
+
+  // Add to page
+  document.body.appendChild(notification);
+
+  // Show notification
+  setTimeout(() => notification.classList.add('show'), 100);
+
+  // Remove notification after 3 seconds
+  setTimeout(() => {
+    notification.classList.remove('show');
+    setTimeout(() => document.body.removeChild(notification), 300);
+  }, 3000);
+}
\ No newline at end of file
diff --git a/routes/approvals.js b/routes/approvals.js
new file mode 100644
index 0000000..491aabb
--- /dev/null
+++ b/routes/approvals.js
@@ -0,0 +1,137 @@
+const express = require('express');
+const auth = require('../middleware/auth');
+const { checkRole, ROLES } = require('../middleware/rbac');
+const approvalService = require('../services/approvalService');
+const router = express.Router();
+
+/**
+ * @route   POST /api/approvals/submit/:expenseId
+ * @desc    Submit expense for approval
+ * @access  Private
+ */
+router.post('/submit/:expenseId', auth, async (req, res) => {
+    try {
+        const workflow = await approvalService.submitForApproval(req.params.expenseId, req.user._id);
+        res.json({
+            success: true,
+            message: 'Expense submitted for approval',
+            data: workflow
+        });
+    } catch (error) {
+        res.status(400).json({ error: error.message });
+    }
+});
+
+/**
+ * @route   GET /api/approvals/pending
+ * @desc    Get pending approvals for current user
+ * @access  Private
+ */
+router.get('/pending', auth, async (req, res) => {
+    try {
+        const approvals = await approvalService.getPendingApprovals(req.user._id);
+        res.json({ success: true, data: approvals });
+    } catch (error) {
+        res.status(500).json({ error: error.message });
+    }
+});
+
+/**
+ * @route   GET /api/approvals/history
+ * @desc    Get approval history for current user
+ * @access  Private
+ */
+router.get('/history', auth, async (req, res) => {
+    try {
+        const page = parseInt(req.query.page) || 1;
+        const limit = parseInt(req.query.limit) || 20;
+        const history = await approvalService.getApprovalHistory(req.user._id, page, limit);
+        res.json({ success: true, data: history });
+    } catch (error) {
+        res.status(500).json({ error: error.message });
+    }
+});
+
+/**
+ * @route   GET /api/approvals/:workflowId
+ * @desc    Get workflow details
+ * @access  Private
+ */
+router.get('/:workflowId', auth, async (req, res) => {
+    try {
+        const workflow = await approvalService.getWorkflowById(req.params.workflowId, req.user._id);
+        res.json({ success: true, data: workflow });
+    } catch (error) {
+        res.status(403).json({ error: error.message });
+    }
+});
+
+/**
+ * @route   POST /api/approvals/:workflowId/approve
+ * @desc    Approve a workflow step
+ * @access  Private
+ */
+router.post('/:workflowId/approve', auth, async (req, res) => {
+    try {
+        const { comments } = req.body;
+        const workflow = await approvalService.processApproval(
+            req.params.workflowId,
+            req.user._id,
+            'approved',
+            comments
+        );
+        res.json({
+            success: true,
+            message: 'Expense approved successfully',
+            data: workflow
+        });
+    } catch (error) {
+        res.status(400).json({ error: error.message });
+    }
+});
+
+/**
+ * @route   POST /api/approvals/:workflowId/reject
+ * @desc    Reject a workflow step
+ * @access  Private
+ */
+router.post('/:workflowId/reject', auth, async (req, res) => {
+    try {
+        const { comments } = req.body;
+        const workflow = await approvalService.processApproval(
+            req.params.workflowId,
+            req.user._id,
+            'rejected',
+            comments
+        );
+        res.json({
+            success: true,
+            message: 'Expense rejected',
+            data: workflow
+        });
+    } catch (error) {
+        res.status(400).json({ error: error.message });
+    }
+});
+
+/**
+ * @route   GET /api/approvals/workspace/:workspaceId
+ * @desc    Get all approval workflows for a workspace (admin only)
+ * @access  Private (Admin only)
+ */
+router.get('/workspace/:workspaceId', auth, checkRole([ROLES.OWNER, ROLES.ADMIN]), async (req, res) => {
+    try {
+        const ApprovalWorkflow = require('../models/ApprovalWorkflow');
+        const workflows = await ApprovalWorkflow.find({ workspaceId: req.params.workspaceId })
+            .populate('expenseId')
+            .populate('submittedBy', 'name email')
+            .populate('steps.approver', 'name email')
+            .sort({ createdAt: -1 });
+
+        res.json({ success: true, data: workflows });
+    } catch (error) {
+        res.status(500).json({ error: error.message });
+    }
+});
+
+module.exports = router;
\ No newline at end of file
diff --git a/routes/expenses.js b/routes/expenses.js
index e0260ec..f835731 100644
--- a/routes/expenses.js
+++ b/routes/expenses.js
@@ -131,10 +131,31 @@ router.post('/', auth, async (req, res) => {
     const expense = new Expense(expenseData);
     await expense.save();
 
+    // Check if expense requires approval
+    const approvalService = require('../services/approvalService');
+    let requiresApproval = false;
+    let workflow = null;
+
+    if (expenseData.workspace) {
+        requiresApproval = await approvalService.requiresApproval(expenseData, expenseData.workspace);
+    }
+
+    if (requiresApproval) {
+        try {
+            workflow = await approvalService.submitForApproval(expense._id, req.user._id);
+            expense.status = 'pending_approval';
+            expense.approvalWorkflow = workflow._id;
+            await expense.save();
+        } catch (approvalError) {
+            console.error('Failed to submit for approval:', approvalError.message);
+            // Continue with normal flow if approval submission fails
+        }
+    }
+
     // Update budget and goal progress using converted amount if available
     const amountForBudget = expenseData.convertedAmount || value.amount;
     if (value.type === 'expense') {
-      await budgetService.checkBudgetAlerts(req.user._id);
+        await budgetService.checkBudgetAlerts(req.user._id);
     }
     await budgetService.updateGoalProgress(req.user._id, value.type === 'expense' ? -amountForBudget : amountForBudget, value.category);
 
@@ -142,7 +163,13 @@ router.post('/', auth, async (req, res) => {
     const io = req.app.get('io');
     io.to(`user_${req.user._id}`).emit('expense_created', expense);
 
-    res.status(201).json(expense);
+    const response = {
+        ...expense.toObject(),
+        requiresApproval,
+        workflow: workflow ? { _id: workflow._id, status: workflow.status } : null
+    };
+
+    res.status(201).json(response);
   } catch (error) {
     res.status(500).json({ error: error.message });
   }
diff --git a/server.js b/server.js
index efeaac6..3561850 100644
--- a/server.js
+++ b/server.js
@@ -216,6 +216,7 @@ app.use('/api/currency', require('./routes/currency'));
 app.use('/api/groups', require('./routes/groups'));
 app.use('/api/splits', require('./routes/splits'));
 app.use('/api/workspaces', require('./routes/workspaces'));
+app.use('/api/approvals', require('./routes/approvals'));
 app.use('/api/investments', require('./routes/investments'));
 app.use('/api/ai', require('./routes/ai'));
 app.use('/api/multicurrency', require('./routes/multicurrency'));
diff --git a/services/approvalService.js b/services/approvalService.js
new file mode 100644
index 0000000..e977475
--- /dev/null
+++ b/services/approvalService.js
@@ -0,0 +1,307 @@
+const ApprovalWorkflow = require('../models/ApprovalWorkflow');
+const Expense = require('../models/Expense');
+const Workspace = require('../models/Workspace');
+const User = require('../models/User');
+const notificationService = require('./notificationService');
+const emailService = require('./emailService');
+
+class ApprovalService {
+    /**
+     * Check if an expense requires approval
+     */
+    async requiresApproval(expenseData, workspaceId = null) {
+        if (!workspaceId) return false;
+
+        const workspace = await Workspace.findById(workspaceId);
+        if (!workspace || !workspace.settings.approvalRequired) return false;
+
+        // Check if expense amount exceeds threshold
+        return expenseData.amount >= workspace.settings.approvalThreshold;
+    }
+
+    /**
+     * Submit expense for approval
+     */
+    async submitForApproval(expenseId, submittedBy) {
+        const expense = await Expense.findById(expenseId).populate('workspace');
+        if (!expense) throw new Error('Expense not found');
+
+        if (!expense.workspace) throw new Error('Expense must belong to a workspace for approval');
+
+        // Check if approval is required
+        const requiresApproval = await this.requiresApproval(expense, expense.workspace._id);
+        if (!requiresApproval) {
+            throw new Error('This expense does not require approval');
+        }
+
+        // Get workspace managers and admins for approval chain
+        const workspace = await Workspace.findById(expense.workspace._id)
+            .populate('members.user', 'name email')
+            .populate('owner', 'name email');
+
+        const approvers = this.getApprovers(workspace);
+
+        if (approvers.length === 0) {
+            throw new Error('No approvers available for this workspace');
+        }
+
+        // Create approval workflow
+        const workflow = new ApprovalWorkflow({
+            workspaceId: expense.workspace._id,
+            expenseId: expense._id,
+            submittedBy: submittedBy,
+            steps: approvers.map((approver, index) => ({
+                stepNumber: index + 1,
+                approver: approver._id,
+                status: index === 0 ? 'pending' : 'pending'
+            })),
+            priority: this.calculatePriority(expense.amount, workspace.settings.approvalThreshold),
+            dueDate: this.calculateDueDate(expense.amount, workspace.settings.approvalThreshold)
+        });
+
+        await workflow.save();
+
+        // Update expense status
+        expense.status = 'pending_approval';
+        await expense.save();
+
+        // Notify first approver
+        await this.notifyApprover(workflow, approvers[0]);
+
+        return workflow;
+    }
+
+    /**
+     * Get list of approvers for a workspace
+     */
+    getApprovers(workspace) {
+        const approvers = [];
+
+        // Add owner as first approver
+        approvers.push(workspace.owner);
+
+        // Add admins and managers
+        workspace.members.forEach(member => {
+            if (['admin', 'manager'].includes(member.role)) {
+                approvers.push(member.user);
+            }
+        });
+
+        // Remove duplicates
+        return [...new Set(approvers.map(a => a._id.toString()))]
+            .map(id => approvers.find(a => a._id.toString() === id));
+    }
+
+    /**
+     * Calculate approval priority based on amount
+     */
+    calculatePriority(amount, threshold) {
+        const ratio = amount / threshold;
+        if (ratio >= 5) return 'urgent';
+        if (ratio >= 2) return 'high';
+        if (ratio >= 1.5) return 'medium';
+        return 'low';
+    }
+
+    /**
+     * Calculate due date based on priority
+     */
+    calculateDueDate(amount, threshold) {
+        const priority = this.calculatePriority(amount, threshold);
+        const now = new Date();
+
+        switch (priority) {
+            case 'urgent': return new Date(now.getTime() + 24 * 60 * 60 * 1000); // 1 day
+            case 'high': return new Date(now.getTime() + 3 * 24 * 60 * 60 * 1000); // 3 days
+            case 'medium': return new Date(now.getTime() + 7 * 24 * 60 * 60 * 1000); // 1 week
+            default: return new Date(now.getTime() + 14 * 24 * 60 * 60 * 1000); // 2 weeks
+        }
+    }
+
+    /**
+     * Process approval decision
+     */
+    async processApproval(workflowId, approverId, decision, comments = '') {
+        const workflow = await ApprovalWorkflow.findById(workflowId)
+            .populate('expenseId')
+            .populate('submittedBy', 'name email')
+            .populate('steps.approver', 'name email');
+
+        if (!workflow) throw new Error('Approval workflow not found');
+
+        if (workflow.status !== 'pending') {
+            throw new Error('Workflow is no longer pending');
+        }
+
+        const currentStep = workflow.steps[workflow.currentStep];
+        if (!currentStep || currentStep.approver._id.toString() !== approverId.toString()) {
+            throw new Error('You are not authorized to approve this request');
+        }
+
+        // Update current step
+        currentStep.status = decision;
+        currentStep.action = decision;
+        currentStep.comments = comments;
+        currentStep.actionDate = new Date();
+
+        if (decision === 'approved') {
+            // Move to next step or complete
+            if (workflow.currentStep < workflow.steps.length - 1) {
+                workflow.currentStep++;
+                const nextStep = workflow.steps[workflow.currentStep];
+                nextStep.status = 'pending';
+                await this.notifyApprover(workflow, nextStep.approver);
+            } else {
+                // All steps approved
+                workflow.status = 'approved';
+                workflow.completedAt = new Date();
+                await this.finalizeApproval(workflow);
+            }
+        } else if (decision === 'rejected') {
+            // Reject the entire workflow
+            workflow.status = 'rejected';
+            workflow.finalComments = comments;
+            workflow.completedAt = new Date();
+            await this.finalizeRejection(workflow);
+        }
+
+        await workflow.save();
+
+        // Notify submitter
+        await this.notifySubmitter(workflow, decision, comments);
+
+        return workflow;
+    }
+
+    /**
+     * Finalize approved expense
+     */
+    async finalizeApproval(workflow) {
+        const expense = await Expense.findById(workflow.expenseId);
+        if (expense) {
+            expense.status = 'approved';
+            await expense.save();
+        }
+
+        // Send notification to submitter
+        await notificationService.createNotification(
+            workflow.submittedBy,
+            'expense_approved',
+            `Your expense "${expense.description}" has been approved`,
+            { expenseId: expense._id, workflowId: workflow._id }
+        );
+    }
+
+    /**
+     * Finalize rejected expense
+     */
+    async finalizeRejection(workflow) {
+        const expense = await Expense.findById(workflow.expenseId);
+        if (expense) {
+            expense.status = 'rejected';
+            await expense.save();
+        }
+
+        // Send notification to submitter
+        await notificationService.createNotification(
+            workflow.submittedBy,
+            'expense_rejected',
+            `Your expense "${expense.description}" has been rejected`,
+            { expenseId: expense._id, workflowId: workflow._id }
+        );
+    }
+
+    /**
+     * Notify approver of pending approval
+     */
+    async notifyApprover(workflow, approver) {
+        const expense = await Expense.findById(workflow.expenseId);
+
+        await notificationService.createNotification(
+            approver._id,
+            'approval_request',
+            `Approval needed for expense: ${expense.description} (₹${expense.amount})`,
+            { expenseId: expense._id, workflowId: workflow._id }
+        );
+
+        // Send email
+        await emailService.sendApprovalRequest(approver.email, {
+            expense: expense,
+            workflow: workflow,
+            approver: approver
+        });
+    }
+
+    /**
+     * Notify submitter of approval decision
+     */
+    async notifySubmitter(workflow, decision, comments) {
+        const expense = await Expense.findById(workflow.expenseId);
+
+        await notificationService.createNotification(
+            workflow.submittedBy,
+            `expense_${decision}`,
+            `Your expense "${expense.description}" has been ${decision}`,
+            { expenseId: expense._id, workflowId: workflow._id, comments }
+        );
+    }
+
+    /**
+     * Get pending approvals for a user
+     */
+    async getPendingApprovals(userId) {
+        return await ApprovalWorkflow.find({
+            'steps.approver': userId,
+            'steps.status': 'pending',
+            status: 'pending'
+        })
+        .populate('expenseId')
+        .populate('submittedBy', 'name email')
+        .populate('workspaceId', 'name')
+        .sort({ createdAt: -1 });
+    }
+
+    /**
+     * Get approval history for a user
+     */
+    async getApprovalHistory(userId, page = 1, limit = 20) {
+        const skip = (page - 1) * limit;
+
+        return await ApprovalWorkflow.find({
+            $or: [
+                { submittedBy: userId },
+                { 'steps.approver': userId }
+            ]
+        })
+        .populate('expenseId')
+        .populate('submittedBy', 'name email')
+        .populate('workspaceId', 'name')
+        .populate('steps.approver', 'name email')
+        .sort({ updatedAt: -1 })
+        .skip(skip)
+        .limit(limit);
+    }
+
+    /**
+     * Get workflow by ID
+     */
+    async getWorkflowById(workflowId, userId) {
+        const workflow = await ApprovalWorkflow.findById(workflowId)
+            .populate('expenseId')
+            .populate('submittedBy', 'name email')
+            .populate('workspaceId', 'name')
+            .populate('steps.approver', 'name email');
+
+        if (!workflow) throw new Error('Workflow not found');
+
+        // Check if user has access
+        const hasAccess = workflow.submittedBy._id.toString() === userId.toString() ||
+                         workflow.steps.some(step => step.approver._id.toString() === userId.toString());
+
+        if (!hasAccess) throw new Error('Access denied');
+
+        return workflow;
+    }
+}
+
+module.exports = new ApprovalService();
\ No newline at end of file