diff --git a/etiquette/constants.py b/etiquette/constants.py
index cb98a6d..552a876 100644
--- a/etiquette/constants.py
+++ b/etiquette/constants.py
@@ -146,6 +146,11 @@ DEFAULT_DATADIR = '.\\_etiquette'
 DEFAULT_CONFIGURATION = {
     'log_level': logging.DEBUG,
 
+    'cache_size_album': 200,
+    'cache_size_photo': 1000,
+    'cache_size_tag': 1000,
+    'cache_size_user': 200,
+
     'enable_new_album': True,
     'enable_new_bookmark': True,
     'enable_new_photo': True,
diff --git a/etiquette/photodb.py b/etiquette/photodb.py
index 9f523d6..3e30732 100644
--- a/etiquette/photodb.py
+++ b/etiquette/photodb.py
@@ -16,6 +16,7 @@ from . import helpers
 from . import objects
 from . import searchhelpers
 
+from voussoirkit import cacheclass
 from voussoirkit import expressionmatch
 from voussoirkit import pathclass
 from voussoirkit import safeprint
@@ -252,6 +253,10 @@ def tag_export_totally_flat(tags):
 
 
 class PDBAlbumMixin:
+    def __init__(self):
+        super().__init__()
+        self._album_cache = cacheclass.Cache()
+
     def get_album(self, id):
         return self.get_thing_by_id('album', id)
 
@@ -346,6 +351,9 @@ class PDBAlbumMixin:
 
 
 class PDBBookmarkMixin:
+    def __init__(self):
+        super().__init__()
+
     def get_bookmark(self, id):
         cur = self.sql.cursor()
         cur.execute('SELECT * FROM bookmarks WHERE id == ?', [id])
@@ -391,6 +399,10 @@ class PDBBookmarkMixin:
 
 
 class PDBPhotoMixin:
+    def __init__(self):
+        super().__init__()
+        self._photo_cache = cacheclass.Cache()
+
     def get_photo(self, photoid):
         return self.get_thing_by_id('photo', photoid)
 
@@ -880,6 +892,10 @@ class PDBPhotoMixin:
 
 
 class PDBTagMixin:
+    def __init__(self):
+        super().__init__()
+        self._tag_cache = cacheclass.Cache()
+
     def export_tags(self, exporter=tag_export_stdout, specific_tag=None):
         '''
         Send the top-level tags to function `exporter`.
@@ -986,6 +1002,10 @@ class PDBTagMixin:
 
 
 class PDBUserMixin:
+    def __init__(self):
+        super().__init__()
+        self._user_cache = cacheclass.Cache()
+
     def generate_user_id(self):
         '''
         User IDs are randomized instead of integers like the other objects,
@@ -1118,6 +1138,8 @@ class PhotoDB(PDBAlbumMixin, PDBBookmarkMixin, PDBPhotoMixin, PDBTagMixin, PDBUs
             self,
             data_directory=None,
         ):
+        super().__init__()
+
         if data_directory is None:
             data_directory = constants.DEFAULT_DATADIR
 
@@ -1172,6 +1194,11 @@ class PhotoDB(PDBAlbumMixin, PDBBookmarkMixin, PDBPhotoMixin, PDBTagMixin, PDBUs
         self.on_commit_queue = []
         self._cached_frozen_children = None
 
+        self._album_cache.maxlen = self.config['cache_size_album']
+        self._photo_cache.maxlen = self.config['cache_size_photo']
+        self._tag_cache.maxlen = self.config['cache_size_tag']
+        self._user_cache.maxlen = self.config['cache_size_user']
+
     def __repr__(self):
         return 'PhotoDB(data_directory={datadir})'.format(datadir=repr(self.data_directory))