diff --git a/lib/stores/memory.js b/lib/stores/memory.js
index 00da94f..dad43dc 100644
--- a/lib/stores/memory.js
+++ b/lib/stores/memory.js
@@ -4,6 +4,8 @@ var memoryStore = function(args) {
     args = args || {};
     var self = {};
     self.name = 'memory';
+    self.usePromises = (typeof Promise === 'undefined' || args.noPromises) ? false : true;
+
     var ttl = args.ttl;
     var lruOpts = {
         max: args.max || 500,
@@ -27,7 +29,7 @@ var memoryStore = function(args) {
         lruCache.set(key, value, maxAge);
         if (cb) {
             process.nextTick(cb);
-        } else {
+        } else if (self.usePromises) {
             return Promise.resolve(value);
         }
     };
@@ -42,6 +44,8 @@ var memoryStore = function(args) {
             process.nextTick(function() {
                 cb(null, value);
             });
+        } else if (self.usePromises) {
+            return Promise.resolve(value);
         } else {
             return value;
         }
@@ -51,9 +55,13 @@ var memoryStore = function(args) {
         if (typeof options === 'function') {
             cb = options;
         }
+
         lruCache.del(key);
+
         if (cb) {
             process.nextTick(cb);
+        } else if (self.usePromises) {
+            return Promise.resolve();
         }
     };
 
@@ -61,6 +69,8 @@ var memoryStore = function(args) {
         lruCache.reset();
         if (cb) {
             process.nextTick(cb);
+        } else if (self.usePromises) {
+            return Promise.resolve();
         }
     };
 
@@ -70,6 +80,8 @@ var memoryStore = function(args) {
             process.nextTick(function() {
                 cb(null, keys);
             });
+        } else if (self.usePromises) {
+            return Promise.resolve(keys);
         } else {
             return keys;
         }
diff --git a/test/caching.unit.js b/test/caching.unit.js
index c43ce7a..67dfcbb 100644
--- a/test/caching.unit.js
+++ b/test/caching.unit.js
@@ -45,6 +45,7 @@ describe("caching", function() {
                 });
 
                 it("lets us set and get data without a callback", function(done) {
+                    cache = caching({store: memoryStore.create({noPromises: true})});
                     cache.set(key, value, {ttl: defaultTtl});
 
                     setTimeout(function() {
@@ -54,7 +55,19 @@ describe("caching", function() {
                     }, 20);
                 });
 
+                it("lets us set and get data without a callback, returning a promise", function(done) {
+                    cache.set(key, value, {ttl: defaultTtl});
+                    setTimeout(function() {
+                        cache.get(key)
+                        .then(function(result) {
+                            assert.equal(result, value);
+                            done();
+                        });
+                    }, 20);
+                });
+
                 it("lets us set and get data without options object or callback", function(done) {
+                    cache = caching({store: memoryStore.create({noPromises: true})});
                     cache.set(key, value);
 
                     setTimeout(function() {
@@ -224,10 +237,11 @@ describe("caching", function() {
 
     describe("keys()", function() {
         var keyCount;
-        var savedKeys = [];
+        var savedKeys;
 
         beforeEach(function(done) {
             keyCount = 10;
+            savedKeys = [];
             var processed = 0;
 
             cache = caching({store: 'memory'});
@@ -248,14 +262,47 @@ describe("caching", function() {
         it("calls back with all keys in cache", function(done) {
             cache.keys(function(err, keys) {
                 checkErr(err);
-                assert.deepEqual(keys.sort, savedKeys.sort);
+                assert.deepEqual(keys.sort(), savedKeys.sort());
                 done();
             });
         });
 
-        it("lets us get the keys without a callback (memory store only)", function() {
-            var keys = cache.keys();
-            assert.deepEqual(keys.sort, savedKeys.sort);
+        it("lets us set and get data without a callback, returning a promise", function(done) {
+            cache.keys()
+            .then(function(keys) {
+                assert.deepEqual(keys.sort(), savedKeys.sort());
+                done();
+            })
+            .catch(function(err) {
+                done(err);
+            });
+        });
+
+        context("when not using promises", function() {
+            beforeEach(function(done) {
+                savedKeys = [];
+                keyCount = 10;
+                var processed = 0;
+
+                cache = caching({store: memoryStore.create({noPromises: true})});
+
+                function isDone() {
+                    return processed === keyCount;
+                }
+
+                async.until(isDone, function(cb) {
+                    processed += 1;
+                    key = support.random.string(20);
+                    savedKeys.push(key);
+                    value = support.random.string();
+                    cache.set(key, value, cb);
+                }, done);
+            });
+
+            it("lets us get the keys without a callback (memory store only)", function() {
+                var keys = cache.keys();
+                assert.deepEqual(keys.sort(), savedKeys.sort());
+            });
         });
     });
 
diff --git a/test/multi_caching.unit.js b/test/multi_caching.unit.js
index 97da932..0bcc2fe 100644
--- a/test/multi_caching.unit.js
+++ b/test/multi_caching.unit.js
@@ -374,7 +374,10 @@ describe("multiCaching", function() {
                 })
                 .then(function() {
                     process.nextTick(function() {
-                        assert.equal(memoryCache.get(key), value);
+                        memoryCache.get(key)
+                        .then(function(fetchedValue) {
+                            assert.equal(fetchedValue, value);
+                        });
                     });
                 })
                 .then(done);
diff --git a/test/stores/memory.unit.js b/test/stores/memory.unit.js
index ab3565d..b031b78 100644
--- a/test/stores/memory.unit.js
+++ b/test/stores/memory.unit.js
@@ -1,3 +1,4 @@
+var assert = require('assert');
 var support = require('../support');
 var memoryStore = require('../../lib/stores/memory');
 
@@ -8,4 +9,22 @@ describe("memory store", function() {
             support.testSetGetDel(memoryCache, done);
         });
     });
+
+    describe("set()", function() {
+        var memoryCache;
+
+        beforeEach(function() {
+            memoryCache = memoryStore.create({noPromises: true});
+        });
+
+        // This test should pass in node v0.10.x:
+        it("does not require a callback or use of Promises", function(done) {
+            memoryCache.set('foo', 'bar');
+
+            setTimeout(function() {
+                assert.equal(memoryCache.get('foo'), 'bar');
+                done();
+            }, 10);
+        });
+    });
 });