diff --git a/test/bodyEncoding.js b/test/bodyEncoding.js
index 22360e2..9bc1d10 100644
--- a/test/bodyEncoding.js
+++ b/test/bodyEncoding.js
@@ -6,6 +6,7 @@ var fs = require('fs');
 var os = require('os');
 var proxy = require('../');
 var startProxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 
 describe('body encoding', function () {
@@ -19,7 +20,7 @@ describe('body encoding', function () {
     server.close();
   });
 
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   var pngHex = '89504e470d0a1a0a0' +
                '000000d4948445200' +
diff --git a/test/catchingErrors.js b/test/catchingErrors.js
index 1bac406..90aba7a 100644
--- a/test/catchingErrors.js
+++ b/test/catchingErrors.js
@@ -4,10 +4,12 @@ var assert = require('assert');
 var express = require('express');
 var request = require('supertest');
 var proxy = require('../');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 describe('when server responds with an error', function () {
 
-  this.timeout(10000);
+  this.timeout(TIMEOUT.QUICK);
 
   var app;
   var slowTarget;
diff --git a/test/constants.js b/test/constants.js
new file mode 100644
index 0000000..50fda00
--- /dev/null
+++ b/test/constants.js
@@ -0,0 +1,18 @@
+'use strict';
+
+/**
+ * Test timeout constants in milliseconds
+ */
+module.exports = {
+  // Standard timeout for most tests
+  STANDARD: 10000,
+
+  // Shorter timeout for quick tests
+  QUICK: 2000,
+
+  // Medium timeout for tests that need a bit more time
+  MEDIUM: 3000,
+
+  // Extended timeout for tests that need more time
+  EXTENDED: 15000
+};
diff --git a/test/cookies.js b/test/cookies.js
index 493f1f0..a7c3c48 100644
--- a/test/cookies.js
+++ b/test/cookies.js
@@ -4,8 +4,9 @@ var assert = require('assert');
 var express = require('express');
 var request = require('supertest');
 var proxy = require('../');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
-var proxyTarget = require('../test/support/proxyTarget');
 var proxyRouteFn = [{
   method: 'get',
   path: '/cookieTest',
@@ -18,7 +19,7 @@ var proxyRouteFn = [{
 }];
 
 describe('proxies cookie', function () {
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   var app;
   var proxyServer;
diff --git a/test/decorateUserResHeaders.js b/test/decorateUserResHeaders.js
index 6fd925b..66e528f 100644
--- a/test/decorateUserResHeaders.js
+++ b/test/decorateUserResHeaders.js
@@ -4,10 +4,11 @@ var assert = require('assert');
 var express = require('express');
 var request = require('supertest');
 var proxy = require('../');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 describe('when userResHeaderDecorator is defined', function () {
-
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   var app;
   var  serverReference;
diff --git a/test/defineMultipleProxyHandlers.js b/test/defineMultipleProxyHandlers.js
index 85a83c4..852d899 100644
--- a/test/defineMultipleProxyHandlers.js
+++ b/test/defineMultipleProxyHandlers.js
@@ -5,6 +5,8 @@ var express = require('express');
 var http = require('http');
 var startProxyTarget = require('./support/proxyTarget');
 var proxy = require('../');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 function fakeProxyServer({path, port, response}) {
   var proxyRouteFn = [{
@@ -37,7 +39,7 @@ function simulateUserRequest() {
 }
 
 describe('handle multiple proxies in the same runtime', function () {
-  this.timeout(3000);
+  this.timeout(TIMEOUT.MEDIUM);
 
   var server;
   var  targetServer, targetServer2;
diff --git a/test/getBody.js b/test/getBody.js
index 8872ea4..fc9f8d4 100644
--- a/test/getBody.js
+++ b/test/getBody.js
@@ -6,6 +6,8 @@ var express = require('express');
 var nock = require('nock');
 var request = require('supertest');
 var proxy = require('../');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 
 function createLocalApplicationServer() {
@@ -14,8 +16,7 @@ function createLocalApplicationServer() {
 }
 
 describe('when proxy request is a GET', function () {
-
-  this.timeout(10000);
+  this.timeout(TIMEOUT.QUICK);
 
   var localServer;
 
diff --git a/test/headers.js b/test/headers.js
index 81a8ddd..31ae730 100644
--- a/test/headers.js
+++ b/test/headers.js
@@ -5,9 +5,10 @@ var express = require('express');
 var request = require('supertest');
 var proxy = require('../');
 var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 describe('proxies headers', function () {
-  this.timeout(2000);
+  this.timeout(TIMEOUT.QUICK);
 
   var http;
   var proxyServer;
diff --git a/test/host.js b/test/host.js
index a42ac24..97e2ca4 100644
--- a/test/host.js
+++ b/test/host.js
@@ -1,12 +1,14 @@
 'use strict';
 
+var assert = require('assert');
 var express = require('express');
 var request = require('supertest');
 var proxy = require('../');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 describe('host can be a dynamic function', function () {
-
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   var app = express();
   describe('and memoization can be disabled', function () {
diff --git a/test/https.js b/test/https.js
index b7b4ac2..3b39b49 100644
--- a/test/https.js
+++ b/test/https.js
@@ -5,9 +5,10 @@ var express = require('express');
 var request = require('supertest');
 var proxy = require('../');
 var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 describe('proxies https', function () {
-  this.timeout(10000);
+  this.timeout(TIMEOUT.QUICK);
 
   var app;
   var proxyServer;
diff --git a/test/maybeSkipToNextHandler.js b/test/maybeSkipToNextHandler.js
index d045a88..666558d 100644
--- a/test/maybeSkipToNextHandler.js
+++ b/test/maybeSkipToNextHandler.js
@@ -5,10 +5,12 @@ var request = require('supertest');
 var proxy = require('../');
 var http = require('http');
 var assert = require('assert');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 describe('when skipToNextHandlerFilter is defined', function () {
 
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   var app;
   var  slowTarget;
diff --git a/test/params.js b/test/params.js
index 94f96aa..72b7a5c 100644
--- a/test/params.js
+++ b/test/params.js
@@ -4,8 +4,9 @@ var assert = require('assert');
 var express = require('express');
 var request = require('supertest');
 var proxy = require('../');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
-var proxyTarget = require('../test/support/proxyTarget');
 var proxyRouteFn = [{
   method: 'get',
   path: '/test',
@@ -15,7 +16,7 @@ var proxyRouteFn = [{
 }];
 
 describe('proxies query parameters', function () {
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   var app;
   var proxyServer;
diff --git a/test/path.js b/test/path.js
index f480e3b..d475dd2 100644
--- a/test/path.js
+++ b/test/path.js
@@ -1,14 +1,16 @@
 'use strict';
 
+var assert = require('assert');
 var express = require('express');
 var request = require('supertest');
 var proxy = require('../');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 var startProxyTarget = require('./support/proxyTarget');
 var expect = require('chai').expect;
 
 describe('uses remote path', function () {
-
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   var app = express();
   var proxyRoutes = ['/somePath/', '/somePath/longer/path', '/somePath/long/path/with/many/tokens'];
@@ -52,10 +54,9 @@ describe('uses remote path', function () {
   });
 });
 
-
 describe('host can be a dynamic function', function () {
 
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   var app = express();
   var firstProxyApp = express();
diff --git a/test/postBody.js b/test/postBody.js
index ebf490f..35389a1 100644
--- a/test/postBody.js
+++ b/test/postBody.js
@@ -6,6 +6,8 @@ var express = require('express');
 var nock = require('nock');
 var request = require('supertest');
 var proxy = require('../');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 
 function createLocalApplicationServer() {
@@ -14,8 +16,7 @@ function createLocalApplicationServer() {
 }
 
 describe('when proxy request is a POST', function () {
-
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   var localServer;
 
diff --git a/test/preserveHostHdr.js b/test/preserveHostHdr.js
index 26cf1e1..be0d6cf 100644
--- a/test/preserveHostHdr.js
+++ b/test/preserveHostHdr.js
@@ -4,8 +4,9 @@ var assert = require('assert');
 var express = require('express');
 var request = require('supertest');
 var proxy = require('../');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
-var proxyTarget = require('../test/support/proxyTarget');
 var proxyRouteFn = [{
   method: 'get',
   path: '/hostHdrTest',
@@ -16,7 +17,7 @@ var proxyRouteFn = [{
 
 describe('preserves host header only when requested', function () {
 
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   var app;
   var proxyServer;
diff --git a/test/proxyReqPathResolver.js b/test/proxyReqPathResolver.js
index 2e0f3bb..7410eb8 100644
--- a/test/proxyReqPathResolver.js
+++ b/test/proxyReqPathResolver.js
@@ -5,14 +5,15 @@ var express = require('express');
 var http = require('http');
 var request = require('supertest');
 var proxy = require('../');
-var proxyTarget = require('../test/support/proxyTarget');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 var aliases = ['forwardPath', 'forwardPathAsync', 'proxyReqPathResolver'];
 
 describe('resolveProxyReqPath', function () {
   var server;
 
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   before(function () {
     var handlers = [{
diff --git a/test/setsContentLength.js b/test/setsContentLength.js
index 827ef52..e7ffb2a 100644
--- a/test/setsContentLength.js
+++ b/test/setsContentLength.js
@@ -6,6 +6,7 @@ var fs = require('fs');
 var os = require('os');
 var proxy = require('../');
 var startProxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 describe('headers: [content-length]', function () {
   var server;
@@ -18,7 +19,7 @@ describe('headers: [content-length]', function () {
     server.close();
   });
 
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   describe('on proxy request', function () {
     it('a `GET` request should have a content-length header, and it should be 0', function (done) {
diff --git a/test/streaming.js b/test/streaming.js
index ab5aef5..dc571ea 100644
--- a/test/streaming.js
+++ b/test/streaming.js
@@ -5,6 +5,8 @@ var express = require('express');
 var http = require('http');
 var startProxyTarget = require('./support/proxyTarget');
 var proxy = require('../');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 function chunkingProxyServer() {
   var proxyRouteFn = [{
@@ -45,7 +47,7 @@ function startLocalServer(proxyOptions) {
 }
 
 describe('streams / piped requests', function () {
-  this.timeout(3000);
+  this.timeout(TIMEOUT.MEDIUM);
 
   var server;
   var  targetServer;
diff --git a/test/urlParsing.js b/test/urlParsing.js
index 339492f..fd39415 100644
--- a/test/urlParsing.js
+++ b/test/urlParsing.js
@@ -4,10 +4,11 @@ var assert = require('assert');
 var express = require('express');
 var request = require('supertest');
 var proxy = require('../');
+var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 describe('url parsing', function () {
-
-  this.timeout(10000);
+  this.timeout(TIMEOUT.STANDARD);
 
   it('can parse a url with a port', function (done) {
     var app = express();
diff --git a/test/userResDecorator.js b/test/userResDecorator.js
index eba8ffc..9440482 100644
--- a/test/userResDecorator.js
+++ b/test/userResDecorator.js
@@ -5,8 +5,10 @@ var express = require('express');
 var request = require('supertest');
 var proxy = require('../');
 var proxyTarget = require('./support/proxyTarget');
+var TIMEOUT = require('./constants');
 
 describe('userResDecorator', function () {
+  this.timeout(TIMEOUT.QUICK);
   var proxyServer;
 
   beforeEach(function () {
@@ -215,6 +217,29 @@ describe('userResDecorator', function () {
         done();
       });
   });
+
+  describe('when userResDecorator returns a Promise', function () {
+    this.timeout(TIMEOUT.EXTENDED);  // give it some extra time to get response
+
+    it('is able to read and manipulate the response', function (done) {
+      var app = express();
+      app.use(proxy('https://github.com/villadora/express-http-proxy', {
+        userResDecorator: function (targetResponse, data) {
+          data = data.toString().replace('DOCTYPE', 'WINNING');
+          assert(data !== '');
+          return data;
+        }
+      }));
+
+      request(app)
+        .get('/html')
+        .end(function (err, res) {
+          if (err) { return done(err); }
+          assert(res.text.indexOf('WINNING') > -1);
+          done();
+        });
+    });
+  });
 });
 
 describe('test userResDecorator on html response from mock server', function () {