diff --git a/README.md b/README.md
index 127495a..b83f09a 100644
--- a/README.md
+++ b/README.md
@@ -53,6 +53,18 @@ These are URLs provided by the third-party website. If you look at the
 OAuth documentation for the site you're authenticating against, it
 should tell you which URLs to use.
 
+Note: If you need to construct the URI at runtime, you can also configure a function
+instead of a string for these parameters:
+
+```clojure
+{:authorize-uri (fn [profile request]
+                   ;; return a URI
+                  )
+ :access-token-uri (fn [profile request]
+                   ;; return a URI
+                  )}
+```
+
 Next is the client ID and secret:
 
 * `:client-id`
diff --git a/src/ring/middleware/oauth2.clj b/src/ring/middleware/oauth2.clj
index 1cfe870..a5be812 100644
--- a/src/ring/middleware/oauth2.clj
+++ b/src/ring/middleware/oauth2.clj
@@ -17,13 +17,16 @@
   (str/join " " (map name (:scopes profile))))
 
 (defn- authorize-uri [profile request state]
-  (str (:authorize-uri profile)
-       (if (.contains ^String (:authorize-uri profile) "?") "&" "?")
-       (codec/form-encode {:response_type "code"
-                           :client_id     (:client-id profile)
-                           :redirect_uri  (redirect-uri profile request)
-                           :scope         (scopes profile)
-                           :state         state})))
+  (let [auth-uri (if (string? (:authorize-uri profile))
+                   (:authorize-uri profile)
+                   ((:authorize-uri profile) profile request))]
+    (str auth-uri
+         (if (.contains ^String auth-uri "?") "&" "?")
+         (codec/form-encode {:response_type "code"
+                             :client_id     (:client-id profile)
+                             :redirect_uri  (redirect-uri profile request)
+                             :scope         (scopes profile)
+                             :state         state}))))
 
 (defn- random-state []
   (-> (random/base64 9) (str/replace "+" "-") (str/replace "/" "_")))
@@ -74,11 +77,14 @@
   [{:keys [access-token-uri client-id client-secret basic-auth?]
     :or {basic-auth? false} :as profile} request]
   (format-access-token
-   (http/post access-token-uri
-     (cond-> {:accept :json, :as  :json,
-              :form-params (request-params profile request)}
-       basic-auth? (add-header-credentials client-id client-secret)
-       (not basic-auth?) (add-form-credentials client-id client-secret)))))
+   (http/post
+    (if (string? access-token-uri)
+      access-token-uri
+      (access-token-uri profile request))
+    (cond-> {:accept :json, :as  :json,
+             :form-params (request-params profile request)}
+      basic-auth? (add-header-credentials client-id client-secret)
+      (not basic-auth?) (add-form-credentials client-id client-secret)))))
 
 (defn state-mismatch-handler [_]
   {:status 400, :headers {}, :body "State mismatch"})
diff --git a/test/ring/middleware/oauth2_test.clj b/test/ring/middleware/oauth2_test.clj
index 033cb87..06675f6 100644
--- a/test/ring/middleware/oauth2_test.clj
+++ b/test/ring/middleware/oauth2_test.clj
@@ -56,6 +56,16 @@
         location  (get-in response [:headers "Location"])]
     (is (.startsWith ^String location "https://example.com/oauth2/authorize?business_partner_id=XXXX&"))))
 
+(deftest test-authorize-uri-as-a-function
+  (let [profile  (assoc test-profile
+                        :authorize-uri
+                        (fn [profile request state]
+                          "https://mycustom-url.example.com/oauth2/authorize"))
+        handler   (wrap-oauth2 token-handler {:test profile})
+        response  (handler (mock/request :get "/oauth2/test"))
+        location  (get-in response [:headers "Location"])]
+    (is (.startsWith ^String location "https://mycustom-url.example.com/oauth2/authorize"))))
+
 (def token-response
   {:status  200
    :headers {"Content-Type" "application/json"}