diff --git a/README.org b/README.org
index 7746a88..97c42fb 100644
--- a/README.org
+++ b/README.org
@@ -43,8 +43,9 @@ The library is implemented around a set of entities.
 | *Name*           | *Type*    | *Fields*             | *Description*                                           |
 |------------------+-----------+----------------------+---------------------------------------------------------|
 | song             | structure | name, album, file, … |                                                         |
-| album            | structure | name, artist         |                                                         |
+| album            | structure | name, date, artists  |                                                         |
 | artist           | structure | name                 |                                                         |
+| genre            | structure | name                 |                                                         |
 | directory        | structure | name, path           |                                                         |
 | stored-playlist  | structure | name                 | A named user-specified sequence of songs                |
 | search-criteria  | structure | type, what           | Read the [[https://www.musicpd.org/doc/protocol/database.html][protocol documentation]]                         |
@@ -52,6 +53,7 @@ The library is implemented around a set of entities.
 |------------------+-----------+----------------------+---------------------------------------------------------|
 | artists          | symbol    | /none/               | Represent the set of all artists                        |
 | albums           | symbol    | /none/               | Represent the set of all albums                         |
+| genres           | symbol    | /none/               | Represent the set of all genres                         |
 | directories      | symbol    | /none/               | Represent all directories in ~libmpdel-music-directory~ |
 | current-playlist | symbol    | /none/               | Represent the currently played sequence of songs        |
 | stored-playlists | symbol    | /none/               | Represent the set of all stored playlists               |
diff --git a/libmpdel.el b/libmpdel.el
index 5db54ba..5f29f4e 100644
--- a/libmpdel.el
+++ b/libmpdel.el
@@ -33,6 +33,7 @@
 (require 'tq)
 (require 'cl-lib)
 (require 'subr-x)
+(require 'seq)
 
 
 ;;; Customization
@@ -171,7 +172,8 @@ message from the server.")
                (:constructor libmpdel--album-create)
                (:conc-name libmpdel--album-))
   (name nil :read-only t)
-  (artist nil :read-only t))
+  (date nil :read-only t)
+  (artists nil :read-only t))
 
 (cl-defstruct (libmpdel-song
                (:constructor libmpdel--song-create)
@@ -180,6 +182,9 @@ message from the server.")
   (track nil :read-only t)
   (file nil :read-only t)
   (album nil :read-only t)
+  (genres nil :read-only t)
+  (performers nil :read-only t)
+  (artists nil :read-only t)
   (disc nil :read-only t)
   (date nil :read-only t)
   (id nil :read-only t)
@@ -190,6 +195,11 @@ message from the server.")
                (:conc-name libmpdel--stored-playlist-))
   (name nil :read-only t))
 
+(cl-defstruct (libmpdel-genre
+               (:constructor libmpdel--genre-create)
+               (:conc-name libmpdel--genre-))
+  (name nil :read-only t))
+
 (cl-defstruct (libmpdel-search-criteria
                (:constructor libmpdel-search-criteria-create)
                (:conc-name libmpdel--search-criteria-))
@@ -205,20 +215,28 @@ message from the server.")
   "Return artist name of ENTITY."
   (libmpdel--artist-name (libmpdel-artist entity)))
 
+(defun libmpdel-artists-name (entity)
+  "Return semicolon separated string of artists names of ENTITY."
+  (string-join (mapcar #'libmpdel--artist-name
+                       (libmpdel-artists entity))
+               "; "))
+
 (cl-defgeneric libmpdel-artist (entity)
-  "Return artist of ENTITY.")
+  "Return artist of ENTITY."
+  (or (car (libmpdel-artists entity))
+      libmpdel--unknown-artist))
 
-(cl-defmethod libmpdel-artist ((artist libmpdel-artist))
-  "Return ARTIST."
-  artist)
+(cl-defmethod libmpdel-artists ((artist libmpdel-artist))
+  "Return singleton list containing ARTIST."
+  (list artist))
 
-(cl-defmethod libmpdel-artist ((album libmpdel-album))
+(cl-defmethod libmpdel-artists ((album libmpdel-album))
   "Return the ALBUM's artist."
-  (libmpdel--album-artist album))
+  (libmpdel--album-artists album))
 
-(cl-defmethod libmpdel-artist ((song libmpdel-song))
-  "Return the SONG's artist."
-  (libmpdel-artist (libmpdel--song-album song)))
+(cl-defmethod libmpdel-artists ((song libmpdel-song))
+  "Return the SONG's artists."
+  (libmpdel--song-artists song))
 
 (defun libmpdel-album-name (entity)
   "Return album name of ENTITY."
@@ -235,6 +253,18 @@ message from the server.")
   "Return SONG's album."
   (libmpdel--song-album song))
 
+(cl-defmethod libmpdel-genres ((song libmpdel-song))
+  "Return SONG's genres."
+  (libmpdel--song-genres song))
+
+(cl-defmethod libmpdel-genres ((genre libmpdel-genre))
+  "Return singleton list GENRE."
+  (list genre))
+
+(cl-defmethod libmpdel-performers ((song libmpdel-song))
+  "Return SONG's performers."
+  (libmpdel--song-performers song))
+
 (cl-defgeneric libmpdel-entity-name (entity)
   "Return the name of ENTITY.")
 
@@ -246,6 +276,10 @@ message from the server.")
   "Return ALBUM's name."
   (libmpdel--album-name album))
 
+(cl-defmethod libmpdel-entity-name ((genre libmpdel-genre))
+  "Return GENRE's name."
+  (libmpdel--genre-name genre))
+
 (cl-defmethod libmpdel-entity-name ((song libmpdel-song))
   "Return SONG's name.
 
@@ -265,6 +299,10 @@ If the SONG's name is nil, return the filename instead."
   "Return a string describing the `albums' entity."
   "All albums")
 
+(cl-defmethod libmpdel-entity-name ((_entity (eql genres)))
+  "Return a string describing the `genres' entity."
+  "All genres")
+
 (cl-defmethod libmpdel-entity-name ((_entity (eql current-playlist)))
   "Return a string describing the `current-playlist' entity."
   "Current playlist")
@@ -295,6 +333,10 @@ If the SONG's name is nil, return the filename instead."
   "Return ALBUM's artist."
   (libmpdel-artist album))
 
+(cl-defmethod libmpdel-entity-parent ((_genre libmpdel-genre))
+  "Return the `genres' entity."
+  'genres)
+
 (cl-defmethod libmpdel-entity-parent ((_artist libmpdel-artist))
   "Return the `artists' entity."
   'artists)
@@ -321,9 +363,16 @@ If the SONG's name is nil, return the filename instead."
   "Return the track number of SONG within its album."
   (or (libmpdel--song-track song) ""))
 
-(defun libmpdel-entity-date (song)
-  "Return the date of SONG."
-  (or (libmpdel--song-date song) ""))
+(cl-defgeneric libmpdel-entity-date (entity)
+  "Return the date of ENTITY.")
+
+(cl-defmethod libmpdel-entity-date ((album libmpdel-album))
+  "Return ALBUM's date."
+  (libmpdel--album-date album))
+
+(cl-defmethod libmpdel-entity-date ((song libmpdel-song))
+  "Return SONG's date."
+  (libmpdel--song-date song))
 
 (defun libmpdel-song-disc (song)
   "Return the disc number of SONG within its album."
@@ -339,15 +388,28 @@ If the SONG's name is nil, return the filename instead."
     (when (and (stringp pos) (not (string= pos "")))
       (string-to-number pos))))
 
+(defun libmpdel--artists-create (artist-names)
+  "Return a list of artists whose names are ARTIST-NAMES."
+  (mapcar (lambda (name)
+            (libmpdel--artist-create :name name))
+          artist-names))
+
+(defun libmpdel--genres-create (genre-names)
+  "Return a list of genres whose names are GENRE-NAMES."
+  (mapcar (lambda (name)
+            (libmpdel--genre-create :name name))
+          genre-names))
+
 (defun libmpdel--create-song-from-data (song-data)
   "Return a song from SONG-DATA, a server's response."
   (libmpdel--song-create
    :name (cdr (assq 'Title song-data))
    :track (cdr (assq 'Track song-data))
    :file (cdr (assq 'file song-data))
-   :album (libmpdel--album-create
-           :name (cdr (assq 'Album song-data))
-           :artist (libmpdel--artist-create :name (cdr (assq 'Artist song-data))))
+   :genres (libmpdel--genres-create (libmpdel-entries song-data 'Genre))
+   :performers (libmpdel--artists-create (libmpdel-entries song-data 'Performer))
+   :artists (libmpdel--artists-create (libmpdel-entries song-data 'Artist))
+   :album (libmpdel--create-album-from-data song-data)
    :date (cdr (assq 'Date song-data))
    :disc (cdr (assq 'Disc song-data))
    :id (cdr (assq 'Id song-data))
@@ -357,6 +419,17 @@ If the SONG's name is nil, return the filename instead."
   "Return a list of songs from DATA, a server's response."
   (mapcar #'libmpdel--create-song-from-data (libmpdel-group-data data)))
 
+(defun libmpdel--create-album-from-data (album-data)
+  "Return an album from ALBUM-DATA, a server's response."
+  (libmpdel--album-create
+   :name (cdr (assq 'Album album-data))
+   :date (cdr (assq 'Date album-data))
+   :artists (libmpdel--artists-create (libmpdel-entries album-data 'AlbumArtist))))
+
+(defun libmpdel--create-albums-from-data (data)
+  "Return a list of albums from DATA, a server's response."
+  (mapcar #'libmpdel--create-album-from-data (libmpdel-group-data data)))
+
 (defun libmpdel-current-playlist-p (entity)
   "Return non-nil if ENTITY is the current playlist."
   (eq entity 'current-playlist))
@@ -920,12 +993,26 @@ If HANDLER is nil, ignore response."
 (cl-defmethod libmpdel-entity-to-criteria ((album libmpdel-album))
   "Return search query matching all songs from ALBUM."
   (format "%s album %S"
-          (libmpdel-entity-to-criteria (libmpdel-artist album))
+          (string-join
+           (mapcar (lambda (artist)
+                     (format "albumartist %S" (libmpdel-entity-name artist)))
+                   (libmpdel-artists album))
+           " ")
           (libmpdel-entity-name album)))
 
+(cl-defmethod libmpdel-entity-to-criteria ((genre libmpdel-genre))
+  "Return search query matching all songs from GENRE."
+  (format "genre %S"
+          (libmpdel-entity-name genre)))
+
 (cl-defmethod libmpdel-entity-to-criteria ((song libmpdel-song))
   "Return search query matching SONG."
-  (format "%s title %S"
+  (format "%s %s title %S"
+          (string-join
+           (mapcar (lambda (artist)
+                     (format "artist %S" (libmpdel-entity-name artist)))
+                   (libmpdel-artists song))
+           " ")
           (libmpdel-entity-to-criteria (libmpdel-album song))
           (libmpdel-entity-name song)))
 
@@ -950,14 +1037,24 @@ If HANDLER is nil, ignore response."
 (cl-defmethod libmpdel-list ((_entity (eql albums)) function)
   "Call FUNCTION with all albums as parameter."
   (libmpdel-send-command
+   ;; TODO: compute all albums by listing all songs
    "list album"
+   (lambda (data)
+     (funcall function
+              (seq-uniq
+               (libmpdel--create-albums-from-data data)
+               #'libmpdel-equal)))))
+
+(cl-defmethod libmpdel-list ((_entity (eql genres)) function)
+  "Call FUNCTION with all genres as parameter."
+  (libmpdel-send-command
+   "list genre"
    (lambda (data)
      (funcall function
               (mapcar
-               (lambda (album-name)
-                 (libmpdel--album-create :name album-name
-                                         :artist libmpdel--unknown-artist))
-               (libmpdel-sorted-entries data 'Album))))))
+               (lambda (genre-name)
+                 (libmpdel--genre-create :name genre-name))
+               (libmpdel-sorted-entries data 'Genre))))))
 
 (cl-defmethod libmpdel-list ((_entity (eql stored-playlists)) function)
   "Call FUNCTION with all stored playlists as parameter."
@@ -972,12 +1069,12 @@ If HANDLER is nil, ignore response."
 (cl-defmethod libmpdel-list ((artist libmpdel-artist) function)
   "Call FUNCTION with all albums of ARTIST as parameter."
   (libmpdel-send-command
-   `("list album %s" ,(libmpdel-entity-to-criteria artist))
+   `("find %s sort AlbumSort" ,(libmpdel-entity-to-criteria artist))
    (lambda (data)
      (funcall function
-              (mapcar
-               (lambda (album-name) (libmpdel--album-create :name album-name :artist artist))
-               (libmpdel-sorted-entries data 'Album))))))
+              (seq-uniq
+               (libmpdel--create-albums-from-data data)
+               #'libmpdel-equal)))))
 
 (cl-defgeneric libmpdel-list-songs (entity function)
   "Call FUNCTION with all songs of ENTITY."
diff --git a/test/libmpdel-test.el b/test/libmpdel-test.el
index 0edad04..01be9ad 100644
--- a/test/libmpdel-test.el
+++ b/test/libmpdel-test.el
@@ -54,23 +54,23 @@
 
 (ert-deftest libmpdel-test-artist ()
   (let* ((artist (libmpdel--artist-create :name "The Artist"))
-         (album (libmpdel--album-create :name "The Album" :artist artist))
-         (song (libmpdel--song-create :name "The song" :album album)))
+         (album (libmpdel--album-create :name "The Album" :artists (list artist)))
+         (song (libmpdel--song-create :name "The song" :album album :artists (list artist))))
     (should (equal artist (libmpdel-artist artist)))
     (should (equal artist (libmpdel-artist album)))
     (should (equal artist (libmpdel-artist song)))))
 
 (ert-deftest libmpdel-test-artist-name ()
   (let* ((artist (libmpdel--artist-create :name "The Artist"))
-         (album (libmpdel--album-create :name "The Album" :artist artist))
-         (song (libmpdel--song-create :name "The song" :album album)))
+         (album (libmpdel--album-create :name "The Album" :artists (list artist)))
+         (song (libmpdel--song-create :name "The song" :album album :artists (list artist))))
     (should (equal "The Artist" (libmpdel-artist-name artist)))
     (should (equal "The Artist" (libmpdel-artist-name album)))
     (should (equal "The Artist" (libmpdel-artist-name song)))))
 
 (ert-deftest libmpdel-test-album-name ()
   (let* ((artist (libmpdel--artist-create :name "The Artist"))
-         (album (libmpdel--album-create :name "The Album" :artist artist))
+         (album (libmpdel--album-create :name "The Album" :artists (list artist)))
          (song (libmpdel--song-create :name "The song" :album album)))
     (should-error (libmpdel-album-name artist))
     (should (equal "The Album" (libmpdel-album-name album)))
@@ -78,7 +78,7 @@
 
 (ert-deftest libmpdel-test-album ()
   (let* ((artist (libmpdel--artist-create :name "The Artist"))
-         (album (libmpdel--album-create :name "The Album" :artist artist))
+         (album (libmpdel--album-create :name "The Album" :artists (list artist)))
          (song (libmpdel--song-create :name "The song" :album album)))
     (should-error (libmpdel-album artist))
     (should (equal album (libmpdel-album album)))
@@ -86,7 +86,7 @@
 
 (ert-deftest libmpdel-test-entity-name ()
   (let* ((artist (libmpdel--artist-create :name "The Artist"))
-         (album (libmpdel--album-create :name "The Album" :artist artist))
+         (album (libmpdel--album-create :name "The Album" :artists (list artist)))
          (song (libmpdel--song-create :name "The song" :album album))
          (stored-playlist (libmpdel--stored-playlist-create :name "The playlist")))
     (should (equal "The Artist" (libmpdel-entity-name artist)))
@@ -101,7 +101,7 @@
 
 (ert-deftest libmpdel-test-entity-parent ()
   (let* ((artist (libmpdel--artist-create :name "The Artist"))
-         (album (libmpdel--album-create :name "The Album" :artist artist))
+         (album (libmpdel--album-create :name "The Album" :artists (list artist)))
          (song (libmpdel--song-create :name "The song" :album album))
          (stored-playlist (libmpdel--stored-playlist-create :name "The playlist")))
     (should (equal 'artists (libmpdel-entity-parent artist)))
@@ -116,12 +116,19 @@
   (let ((song (libmpdel--create-song-from-data
                '((Title . "The song")
                  (file . "foo/song.ogg")
+                 (Date . "1970-01-01")
                  (Album . "The Album")
+                 (AlbumArtist . "The Albumartist")
+                 (Genre . "The Genre")
                  (Artist . "The Artist")))))
     (should (equal "The song" (libmpdel-entity-name song)))
     (should (equal "foo/song.ogg" (libmpdel-song-file song)))
+    (should (equal "1970-01-01" (libmpdel-entity-date song)))
+    (should (equal "1970-01-01" (libmpdel-entity-date (libmpdel-album song))))
+    (should (equal (list "The Genre") (mapcar #'libmpdel-entity-name (libmpdel-genres song))))
     (should (equal "The Album" (libmpdel-entity-name (libmpdel-album song))))
-    (should (equal "The Artist" (libmpdel-entity-name (libmpdel-artist (libmpdel-album song)))))))
+    (should (equal "The Artist" (libmpdel-entity-name (libmpdel-artist song))))
+    (should (equal "The Albumartist" (libmpdel-entity-name (libmpdel-artist (libmpdel-album song)))))))
 
 (ert-deftest libmpdel-test-current-playlist-p ()
   (should (libmpdel-current-playlist-p 'current-playlist))
@@ -269,20 +276,22 @@
 
 (ert-deftest libmpdel-test-playlist-add-no-string-id-sends-findadd ()
   (let* ((artist (libmpdel--artist-create :name "The Artist"))
-         (album (libmpdel--album-create :name "The Album" :artist artist)))
+         (album (libmpdel--album-create :name "The Album" :artists (list artist))))
    (libmpdel-test--with-connection
     (libmpdel-playlist-add album 'current-playlist)
-    (should (equal '("findadd artist \"The Artist\" album \"The Album\"")
+    (should (equal '("findadd albumartist \"The Artist\" album \"The Album\"")
                    (last commands))))))
 
 (ert-deftest libmpdel-test-playlist-add-sends-findadd ()
  (let ((song (libmpdel--create-song-from-data
                '((Title . "S")
                  (Album . "A")
+                 (AlbumArtist . "Art")
+                 (AlbumArtist . "Bart")
                  (Artist . "Art")))))
    (libmpdel-test--with-connection
     (libmpdel-playlist-add song 'current-playlist)
-    (should (equal '("findadd artist \"Art\" album \"A\" title \"S\"")
+    (should (equal '("findadd artist \"Art\" albumartist \"Art\" albumartist \"Bart\" album \"A\" title \"S\"")
                    (last commands))))))
 
 
@@ -323,9 +332,9 @@
   (let* ((artist1 (libmpdel--artist-create :name "artist1"))
          (artist1-bis (libmpdel--artist-create :name "artist1"))
          (artist2 (libmpdel--artist-create :name "artist2"))
-         (album1 (libmpdel--album-create :name "album1" :artist artist1))
-         (album1-bis (libmpdel--album-create :name "album1" :artist artist1))
-         (album2 (libmpdel--album-create :name "album2" :artist artist1))
+         (album1 (libmpdel--album-create :name "album1" :artists (list artist1)))
+         (album1-bis (libmpdel--album-create :name "album1" :artists (list artist1)))
+         (album2 (libmpdel--album-create :name "album2" :artists (list artist1)))
          (song1 (libmpdel--song-create
                  :name "name"
                  :file "file"