diff --git a/src/clj/clojure/walk.clj b/src/clj/clojure/walk.clj
index 0d9e0e1802..f4896dbdbf 100644
--- a/src/clj/clojure/walk.clj
+++ b/src/clj/clojure/walk.clj
@@ -90,21 +90,25 @@ the sorting function."}
   [form]
   (prewalk (fn [x] (print "Walked: ") (prn x) x) form))
 
+(defn transform-keys
+  "Recursively transform all map keys using f as a transformation function."
+  {:added "1.9"}
+  [m f]
+  (let [entry-f (fn [[k v]] [(f k) v])]
+    ;; only apply to maps
+    (postwalk (fn [x] (if (map? x) (into {} (map entry-f x)) x)) m)))
+
 (defn keywordize-keys
   "Recursively transforms all map keys from strings to keywords."
   {:added "1.1"}
   [m]
-  (let [f (fn [[k v]] (if (string? k) [(keyword k) v] [k v]))]
-    ;; only apply to maps
-    (postwalk (fn [x] (if (map? x) (into {} (map f x)) x)) m)))
+  (transform-keys m (fn [k] (if (string? k) (keyword k) k))))
 
 (defn stringify-keys
   "Recursively transforms all map keys from keywords to strings."
   {:added "1.1"}
   [m]
-  (let [f (fn [[k v]] (if (keyword? k) [(name k) v] [k v]))]
-    ;; only apply to maps
-    (postwalk (fn [x] (if (map? x) (into {} (map f x)) x)) m)))
+  (transform-keys m (fn [k] (if (keyword? k) (name k) k))))
 
 (defn prewalk-replace
   "Recursively transforms form by replacing keys in smap with their
diff --git a/test/clojure/test_clojure/clojure_walk.clj b/test/clojure/test_clojure/clojure_walk.clj
index 115ae34318..a62522ebf6 100644
--- a/test/clojure/test_clojure/clojure_walk.clj
+++ b/test/clojure/test_clojure/clojure_walk.clj
@@ -14,6 +14,14 @@
   (is (= (w/stringify-keys {:a 1, nil {:b 2 :c 3}, :d 4})
          {"a" 1, nil {"b" 2 "c" 3}, "d" 4})))
 
+(deftest t-transform-keys
+  (is (= (w/transform-keys {:a 1, nil {:b 2 :c 3}, :d 4, :e 5}
+                          (fn [k]
+                             (if (keyword? k)
+                               (str (name k) "-" (name k))
+                               k)))
+         {"a-a" 1, nil {"b-b" 2 "c-c" 3}, "d-d" 4, "e-e" 5})))
+
 (deftest t-prewalk-order
   (is (= (let [a (atom [])]
            (w/prewalk (fn [form] (swap! a conj form) form)