diff --git a/classes/ComponentHelper.php b/classes/ComponentHelper.php
index 7582e6e..a59216c 100644
--- a/classes/ComponentHelper.php
+++ b/classes/ComponentHelper.php
@@ -5,6 +5,7 @@
 use Exception;
 use Winter\Storm\Support\Traits\Singleton;
 use ApplicationException;
+use Lang;
 
 /**
  * Provides helper methods for Builder CMS components.
@@ -64,7 +65,7 @@ public function getModelClassDesignTime()
         $modelClass = trim(Input::get('modelClass'));
 
         if ($modelClass && !is_scalar($modelClass)) {
-            throw new ApplicationException('Model class name should be a string.');
+            throw new ApplicationException(Lang::get('winter.builder::lang.components.error_model_class_name_should_be_a_string'));
         }
 
         if (!strlen($modelClass)) {
@@ -73,7 +74,7 @@ public function getModelClassDesignTime()
         }
 
         if (!ModelModel::validateModelClassName($modelClass)) {
-            throw new ApplicationException('Invalid model class name.');
+            throw new ApplicationException(Lang::get('winter.builder::lang.components.error_invalid_model_class_name'));
         }
 
         return $modelClass;
diff --git a/classes/IndexOperationsBehaviorBase.php b/classes/IndexOperationsBehaviorBase.php
index cfa0c85..f395f4d 100644
--- a/classes/IndexOperationsBehaviorBase.php
+++ b/classes/IndexOperationsBehaviorBase.php
@@ -3,6 +3,7 @@
 use Backend\Classes\ControllerBehavior;
 use Backend\Behaviors\FormController;
 use ApplicationException;
+use Lang;
 
 /**
  * Base class for index operation behaviors
@@ -17,7 +18,7 @@ abstract class IndexOperationsBehaviorBase extends ControllerBehavior
     protected function makeBaseFormWidget($modelCode, $options = [], $aliasSuffix = null)
     {
         if (!strlen($this->baseFormConfigFile)) {
-            throw new ApplicationException(sprintf('Base form configuration file is not specified for %s behavior', get_class($this)));
+            throw new ApplicationException(Lang::get('winter.builder::lang.behavior.error_base_form_configuration_file_is_not_specified', ['class' => get_class($this)]));
         }
 
         $widgetConfig = $this->makeConfig($this->baseFormConfigFile);
@@ -36,7 +37,7 @@ protected function getPluginCode()
         $vector = $this->controller->getBuilderActivePluginVector();
 
         if (!$vector) {
-            throw new ApplicationException('Cannot determine the currently active plugin.');
+            throw new ApplicationException(Lang::get('winter.builder::lang.behavior.error_cannot_determine_currently_active_plugin'));
         }
 
         return $vector->pluginCodeObj;
diff --git a/classes/LanguageMixer.php b/classes/LanguageMixer.php
index aa871c0..6abd597 100644
--- a/classes/LanguageMixer.php
+++ b/classes/LanguageMixer.php
@@ -3,6 +3,7 @@
 use Yaml;
 use Symfony\Component\Yaml\Dumper as YamlDumper;
 use ApplicationException;
+use Lang;
 
 class LanguageMixer
 {
@@ -28,7 +29,7 @@ public function addStringsFromAnotherLanguage($destContents, $srcArray)
             $destArray = Yaml::parse($destContents);
         }
         catch (Exception $ex) {
-            throw new ApplicationException(sprintf('Cannot parse the YAML content: %s', $ex->getMessage()));
+            throw new ApplicationException(Lang::get('winter.builder::lang.localization.error_cannot_parse_yaml', ['message' => $ex->getMessage()]));
         }
 
         if (!$destArray) {
diff --git a/classes/LocalizationModel.php b/classes/LocalizationModel.php
index a0720d3..042e2d4 100644
--- a/classes/LocalizationModel.php
+++ b/classes/LocalizationModel.php
@@ -118,7 +118,7 @@ public function save()
     public function deleteModel()
     {
         if ($this->isNewModel()) {
-            throw new ApplicationException('Cannot delete language file which is not saved yet.');
+            throw new ApplicationException(Lang::get('winter.builder::lang.localization.error_cannot_delete_lang_file_which_is_not_saved'));
         }
 
         $filePath = File::symbolizePath($this->getFilePath());
@@ -227,7 +227,7 @@ public static function getDefaultLanguage()
         $language = Config::get('app.locale');
 
         if (!$language) {
-            throw new ApplicationException('The default language is not defined in the application configuration (app.locale).');
+            throw new ApplicationException(Lang::get('winter.builder::lang.localization.error_default_language_is_not_defined'));
         }
 
         return $language;
@@ -333,7 +333,7 @@ protected function getFilePath($language = null)
         }
 
         if (!$this->validateLanguage($language)) {
-            throw new SystemException('Invalid language file name: '.$language);
+            throw new SystemException('Invalid language file name: ' . $language);
         }
 
         $path = $this->getPluginCodeObj()->toPluginDirectoryPath().'/lang/'.$language.'/lang.php';
@@ -364,7 +364,7 @@ protected function modelToLanguageFile()
             return "<?php return ".$phpData.";";
         }
         catch (Exception $ex) {
-            throw new ApplicationException(sprintf('Cannot parse the YAML content: %s', $ex->getMessage()));
+            throw new ApplicationException(Lang::get('winter.builder::lang.localization.error_cannot_parse_yaml'), ['message' => $ex->getMessage()]);
         }
     }
 
diff --git a/classes/MenusModel.php b/classes/MenusModel.php
index 9c5c4de..042d031 100644
--- a/classes/MenusModel.php
+++ b/classes/MenusModel.php
@@ -35,7 +35,7 @@ protected function modelToYamlArray()
             $mainMenuItem = $this->trimMenuProperties($mainMenuItem);
 
             if (!isset($mainMenuItem['code'])) {
-                throw new ApplicationException('Cannot save menus - the main menu item code should not be empty.');
+                throw new ApplicationException(Lang::get('winter.builder::lang.menu.error_main_menu_item_code_should_not_be_empty'));
             }
 
             if (isset($mainMenuItem['sideMenu'])) {
@@ -45,7 +45,7 @@ protected function modelToYamlArray()
                     $sideMenuItem = $this->trimMenuProperties($sideMenuItem);
 
                     if (!isset($sideMenuItem['code'])) {
-                        throw new ApplicationException('Cannot save menus - the side menu item code should not be empty.');
+                        throw new ApplicationException(Lang::get('winter.builder::lang.menu.error_side_menu_item_code_should_not_be_empty'));
                     }
 
                     $code = $sideMenuItem['code'];
diff --git a/classes/MigrationModel.php b/classes/MigrationModel.php
index 2a87a0d..4ab5d35 100644
--- a/classes/MigrationModel.php
+++ b/classes/MigrationModel.php
@@ -151,12 +151,12 @@ public function load($versionNumber)
         $versionNumber = trim($versionNumber);
 
         if (!strlen($versionNumber)) {
-            throw new ApplicationException('Cannot load the the version model - the version number should not be empty.');
+            throw new ApplicationException(Lang::get('winter.builder::lang.migration.error_cannot_load_version_model_should_not_be_empty'));
         }
 
         $pluginVersions = $this->getPluginVersionInformation();
         if (!array_key_exists($versionNumber, $pluginVersions)) {
-            throw new ApplicationException('The requested version does not exist in the version information file.');
+            throw new ApplicationException(Lang::get('winter.builder::lang.migration.error_requested_version_does_not_exist'));
         }
 
         $this->version = $versionNumber;
@@ -171,7 +171,7 @@ public function load($versionNumber)
             $cnt = count($versionInformation);
 
             if ($cnt > 2) {
-                throw new ApplicationException('The requested version cannot be edited with Builder as it refers to multiple PHP scripts.');
+                throw new ApplicationException(Lang::get('winter.builder::lang.migration.error_requested_version_cannot_be_edited'));
             }
 
             if ($cnt > 0) {
@@ -373,7 +373,7 @@ protected function loadScriptFile()
         $scriptFilePath = $this->getPluginUpdatesPath($this->scriptFileName.'.php');
 
         if (!File::isFile($scriptFilePath)) {
-            throw new ApplicationException(sprintf('Version file %s is not found.', $scriptFilePath));
+            throw new ApplicationException(Lang::get('winter.builder::lang.migration.error_version_file_is_not_found', ['path' => $scriptFilePath]));
         }
 
         return File::get($scriptFilePath);
diff --git a/classes/ModelFormModel.php b/classes/ModelFormModel.php
index 2a90dd9..8c80253 100644
--- a/classes/ModelFormModel.php
+++ b/classes/ModelFormModel.php
@@ -2,6 +2,7 @@
 
 use SystemException;
 use ValidationException;
+use Lang;
 
 /**
  * Represents and manages model forms.
@@ -131,7 +132,7 @@ public function validate()
         parent::validate();
 
         if (!$this->controls) {
-            throw new ValidationException(['controls' => 'Please create at least one field.']);
+            throw new ValidationException(['controls' => Lang::get('winter.builder::lang.form.validation_create_at_least_one_field')]);
         }
     }
 
diff --git a/classes/ModelListModel.php b/classes/ModelListModel.php
index 035fc43..89f86d1 100644
--- a/classes/ModelListModel.php
+++ b/classes/ModelListModel.php
@@ -37,7 +37,7 @@ public function fill(array $attributes)
             $attributes['columns'] = json_decode($attributes['columns'], true);
 
             if ($attributes['columns'] === null) {
-                throw new SystemException('Cannot decode columns JSON string.');
+                throw new SystemException('Cannot decode columns JSON string.'));
             }
         }
 
@@ -66,7 +66,7 @@ public function validate()
         $this->validateDupicateColumns();
 
         if (!$this->columns) {
-            throw new ValidationException(['columns' => 'Please create at least one column.']);
+            throw new ValidationException(['columns' => Lang::get('winter.builder::lang.list.validation_columns_create_at_least_one_column')]);
         }
     }
 
@@ -101,7 +101,7 @@ protected function modelToYamlArray()
 
         foreach ($this->columns as $column) {
             if (!isset($column['field'])) {
-                throw new ApplicationException('Cannot save the list - the column field name should not be empty.');
+                throw new ApplicationException(Lang::get('winter.builder::lang.list.error_name_should_not_be_empty'));
             }
 
             $columnName = $column['field'];
diff --git a/classes/ModelModel.php b/classes/ModelModel.php
index 7f93afa..c6ef4ec 100644
--- a/classes/ModelModel.php
+++ b/classes/ModelModel.php
@@ -306,7 +306,7 @@ public static function getModelColumnsAndTypes($pluginCodeObj, $modelClassName)
         $tableName = self::getTableNameFromModelClass($pluginCodeObj, $modelClassName);
 
         if (!DatabaseTableModel::tableExists($tableName)) {
-            throw new ApplicationException('Database table not found: '.$tableName);
+            throw new ApplicationException(Lang::get('winter.builder::lang.model.error_db_table_not_found', ['table' => $tableName]));
         }
 
         $schema = DatabaseTableModel::getSchema();
diff --git a/classes/PermissionsModel.php b/classes/PermissionsModel.php
index 90e66e2..0e48f94 100644
--- a/classes/PermissionsModel.php
+++ b/classes/PermissionsModel.php
@@ -48,7 +48,7 @@ protected function modelToYamlArray()
             }
 
             if (!isset($permission['permission'])) {
-                throw new ApplicationException('Cannot save permissions - the permission code should not be empty.');
+                throw new ApplicationException(Lang::get('winter.builder::lang.permission.error_save_permissions_code_should_not_be_empty'));
             }
 
             $code = $permission['permission'];
diff --git a/classes/PluginCode.php b/classes/PluginCode.php
index 7fba203..82ebca5 100644
--- a/classes/PluginCode.php
+++ b/classes/PluginCode.php
@@ -1,6 +1,7 @@
 <?php namespace Winter\Builder\Classes;
 
 use ApplicationException;
+use Lang;
 
 /**
  * Represents a plugin code and provides basic code operations.
@@ -18,13 +19,13 @@ public function __construct($pluginCodeStr)
     {
         $codeParts = explode('.', $pluginCodeStr);
         if (count($codeParts) !== 2) {
-            throw new ApplicationException(sprintf('Invalid plugin code: %s', $pluginCodeStr));
+            throw new ApplicationException(Lang::get('winter.builder::lang.plugin.error_invalid_plugin_code', ['code' => $pluginCodeStr]));
         }
 
         list($authorCode, $pluginCode) = $codeParts;
 
         if (!$this->validateCodeWord($authorCode) || !$this->validateCodeWord($pluginCode)) {
-            throw new ApplicationException(sprintf('Invalid plugin code: %s', $pluginCodeStr));
+            throw new ApplicationException(Lang::get('winter.builder::lang.plugin.error_invalid_plugin_code', ['code' => $pluginCodeStr]));
         }
 
         $this->authorCode = trim($authorCode);
@@ -35,7 +36,7 @@ public static function createFromNamespace($namespace)
     {
         $namespaceParts = explode('\\', $namespace);
         if (count($namespaceParts) < 2) {
-            throw new ApplicationException('Invalid plugin namespace value.');
+            throw new ApplicationException(Lang::get('winter.builder::lang.plugin.error_invalid_plugin_namespace'));
         }
 
         $authorCode = $namespaceParts[0];
diff --git a/classes/YamlModel.php b/classes/YamlModel.php
index 79d9023..d9992df 100644
--- a/classes/YamlModel.php
+++ b/classes/YamlModel.php
@@ -102,14 +102,14 @@ protected function load($filePath)
         $filePath = File::symbolizePath($filePath);
 
         if (!File::isFile($filePath)) {
-            throw new ApplicationException('Cannot load the model - the original file is not found: '.basename($filePath));
+            throw new ApplicationException(Lang::get('winter.builder::lang.yaml.error_cannot_load_model_file_is_not_found', ['path' => basename($filePath)]));
         }
 
         try {
             $data = Yaml::parse(File::get($filePath));
         }
         catch (Exception $ex) {
-            throw new ApplicationException(sprintf('Cannot parse the YAML file %s: %s', basename($filePath), $ex->getMessage()));
+            throw new ApplicationException(Lang::get('winter.builder::lang.yaml.error_cannot_parse_yaml_file', ['path' => basename($filePath), 'message' => $ex->getMessage()]));
         }
 
         $this->originalFilePath = $filePath;
@@ -134,11 +134,11 @@ protected function load($filePath)
     public function deleteModel()
     {
         if (!File::isFile($this->originalFilePath)) {
-            throw new ApplicationException('Cannot load the model - the original file is not found: '.$filePath);
+            throw new ApplicationException(Lang::get('winter.builder::lang.yaml.error_cannot_load_model_file_is_not_found', ['path' => $filePath]));
         }
 
         if (strtolower(substr($this->originalFilePath, -5)) !== '.yaml') {
-            throw new ApplicationException('Cannot delete the model - the original file should be a YAML document');
+            throw new ApplicationException(Lang::get('winter.builder::lang.yaml.error_cannot_delete_model_file_should_be_yaml'));
         }
 
         File::delete($this->originalFilePath);
diff --git a/lang/en/lang.php b/lang/en/lang.php
index 239792f..59dc6be 100644
--- a/lang/en/lang.php
+++ b/lang/en/lang.php
@@ -33,6 +33,8 @@
         'replaces_prompt' => 'Add a plugin',
         'replaces_plugin_code' => 'Plugin code',
         'replaces_plugin_constraint' => 'Version constraint',
+        'error_invalid_plugin_code' => 'Invalid plugin code: :code',
+        'error_invalid_plugin_namespace' => 'Invalid plugin namespace value.',
     ],
     'author_name' => [
         'title' => 'Author name',
@@ -110,6 +112,7 @@
         'error_deleted_at_column_must_exist' => 'The database table must have deleted_at column.',
         'add_form' => 'Add form',
         'add_list' => 'Add list',
+        'error_db_table_not_found' => 'Database table not found: :table',
         'delete_model' => 'Delete model :model',
         'delete_model_confirm' => 'Are you sure you wish to delete the ":model" model? This will also remove any forms and lists connected to the model.',
         'deleted' => 'Model ":model" successfully deleted.',
@@ -399,6 +402,7 @@
         'tab_css_class_description' => 'Assigns a CSS class to the tabs container.',
         'tab_name_template' => 'Tab %s',
         'tab_already_exists' => 'Tab with the specified title already exists.',
+        'validation_create_at_least_one_field' => 'Please create at least one field.',
     ],
     'list' => [
         'tab_new_list' => 'New list',
@@ -437,7 +441,9 @@
         'column_label_value_from' => 'Value from',
         'error_duplicate_column' => "Duplicate column field name: ':column'.",
         'btn_add_database_columns' => 'Add database columns',
-        'all_database_columns_exist' => 'All database columns are already defined in the list'
+        'all_database_columns_exist' => 'All database columns are already defined in the list',
+        'validation_columns_create_at_least_one_column' => 'Please create at least one column.',
+        'error_name_should_not_be_empty' => 'Cannot save the list - the column field name should not be empty.',
     ],
     'controller' => [
         'menu_label' => 'Controllers',
@@ -611,6 +617,8 @@
         'property_code_required' => 'Please enter the menu item code.',
         'error_duplicate_main_menu_code' => "Duplicate main menu item code: ':code'.",
         'error_duplicate_side_menu_code' => "Duplicate side menu item code: ':code'.",
+        'error_main_menu_item_code_should_not_be_empty' => 'Cannot save menus - the main menu item code should not be empty.',
+        'error_side_menu_item_code_should_not_be_empty' => 'Cannot save menus - the side menu item code should not be empty.',
     ],
     'localization' => [
         'menu_label' => 'Localization',
@@ -639,6 +647,9 @@
         'string_key_is_a_string' => ':key is a string and cannot contain other strings.',
         'string_value_is_empty' => 'String value should not be empty',
         'string_key_exists' => 'The string key already exists',
+        'error_cannot_delete_lang_file_which_is_not_saved' => 'Cannot delete language file which is not saved yet.',
+        'error_default_language_is_not_defined' => 'The default language is not defined in the application configuration (app.locale).',
+        'error_cannot_parse_yaml' => 'Cannot parse the YAML content: :message',
     ],
     'permission' => [
         'menu_label' => 'Permissions',
@@ -654,9 +665,14 @@
         'column_label_required' => 'Please enter the permission label',
         'saved' => 'Permissions saved',
         'error_duplicate_code' => "Duplicate permission code: ':code'.",
+        'error_save_permissions_code_should_not_be_empty' => 'Cannot save permissions - the permission code should not be empty.',
     ],
     'yaml' => [
         'save_error' => "Error saving file ':name'. Please check write permissions.",
+        'error_cannot_load_model_file_is_not_found' => 'Cannot load the model - the original file is not found: :path',
+        'error_cannot_parse_yaml_file' => 'Cannot parse the YAML file :path: :message',
+        'error_cannot_load_model_file_is_not_found' => 'Cannot load the model - the original file is not found: :path',
+        'error_cannot_delete_model_file_should_be_yaml' => 'Cannot delete the model - the original file should be a YAML document',
     ],
     'common' => [
         'error_file_exists' => "File already exists: ':path'.",
@@ -687,6 +703,10 @@
         'error_namespace_mismatch' => "The migration code should use the plugin namespace: :namespace",
         'error_migration_file_exists' => "Migration file :file already exists. Please use another class name.",
         'error_cant_delete_applied' => 'This version has already been applied and cannot be deleted. Please rollback the version first.',
+        'error_cannot_load_version_model_should_not_be_empty' => 'Cannot load the version model - the version number should not be empty.',
+        'error_requested_version_does_not_exist' => 'The requested version does not exist in the version information file.',
+        'error_requested_version_cannot_be_edited' => 'The requested version cannot be edited with Builder as it refers to multiple PHP scripts.',
+        'error_version_file_is_not_found' => 'Version file :path is not found',
     ],
     'components' => [
         'list_title' => 'Record list',
@@ -738,12 +758,18 @@
         'details_not_found_message' => 'Not found message',
         'details_not_found_message_description' => 'Message to display if the record is not found. Used in the default component\'s partial.',
         'details_not_found_message_default' => 'Record not found',
+        'error_invalid_model_class_name' => 'Invalid model class name.',
+        'error_model_class_name_should_be_a_string' => 'Model class name should be a string.',
     ],
     'validation' => [
-        'reserved' => ':attribute cannot be a PHP reserved keyword'
+        'reserved' => ':attribute cannot be a PHP reserved keyword',
+    ],
+    'behavior' => [
+        'error_base_form_configuration_file_is_not_specified' => 'Base form configuration file is not specified for :class behavior',
+        'error_cannot_determine_currently_active_plugin' => 'Cannot determine the currently active plugin.',
     ],
     'settings' => [
-        'menu_desc' => 'Set your author name and namespace for plugin creation.'
+        'menu_desc' => 'Set your author name and namespace for plugin creation.',
     ],
     'welcome' => [
         'heading' => 'Welcome to the Builder.',