diff --git a/.travis.yml b/.travis.yml
index ac5cef39..728e6689 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,7 +6,7 @@ python:
 
 os:
   - linux
-#  - osx
+
 
 sudo: false
 
diff --git a/karma-tests/karma.conf.js b/karma-tests/karma.conf.js
index 61127d7d..b40190f2 100644
--- a/karma-tests/karma.conf.js
+++ b/karma-tests/karma.conf.js
@@ -1,18 +1,56 @@
+if (!process.env['SAUCE_USERNAME'] || !process.env['SAUCE_ACCESS_KEY']) {
+    console.error('Sauce Labs account details not set, skipping Karma tests');
+    process.exit(0);
+}
+
+var sauceLabsConfig = {
+    testName: 'PyWB Client Tests',
+};
+
+// see https://github.com/karma-runner/karma-sauce-launcher/issues/73
+if (process.env.TRAVIS_JOB_NUMBER) {
+    sauceLabsConfig.startConnect = false;
+    sauceLabsConfig.tunnelIdentifier = process.env.TRAVIS_JOB_NUMBER;
+}
+
 var WOMBAT_JS_PATH = 'pywb/static/wombat.js';
 
+var customLaunchers = {
+    sl_chrome: {
+        base: 'SauceLabs',
+        browserName: 'chrome',
+    },
+
+    sl_firefox: {
+        base: 'SauceLabs',
+        browserName: 'firefox',
+    },
+
+/*  Safari and Edge are currently broken in
+    pywb.
+
+    See: https://github.com/ikreymer/pywb/issues/148 (Edge)
+         https://github.com/ikreymer/pywb/issues/147 (Safari)
+
+    sl_safari: {
+        base: 'SauceLabs',
+        browserName: 'safari',
+        platform: 'OS X 10.11',
+        version: '9.0',
+    },
+    sl_edge: {
+        base: 'SauceLabs',
+        browserName: 'MicrosoftEdge',
+    },
+*/
+};
+
 module.exports = function(config) {
   config.set({
-
-    // base path that will be used to resolve all patterns (eg. files, exclude)
     basePath: '../',
 
-
-    // frameworks to use
-    // available frameworks: https://npmjs.org/browse/keyword/karma-adapter
     frameworks: ['mocha', 'chai'],
 
-
-    // list of files / patterns to load in the browser
     files: [
       {
         pattern: WOMBAT_JS_PATH,
@@ -23,46 +61,30 @@ module.exports = function(config) {
       'karma-tests/*.spec.js',
     ],
 
-
-    // preprocess matching files before serving them to the browser
-    // available preprocessors: https://npmjs.org/browse/keyword/karma-preprocessor
     preprocessors: {},
 
-
-    // test results reporter to use
-    // possible values: 'dots', 'progress'
-    // available reporters: https://npmjs.org/browse/keyword/karma-reporter
     reporters: ['progress'],
 
-
-    // web server port
     port: 9876,
 
-
-    // enable / disable colors in the output (reporters and logs)
     colors: true,
 
-
-    // level of logging
-    // possible values: config.LOG_DISABLE || config.LOG_ERROR || config.LOG_WARN || config.LOG_INFO || config.LOG_DEBUG
     logLevel: config.LOG_INFO,
 
-
-    // enable / disable watching file and executing tests whenever any file changes
     autoWatch: true,
 
+    sauceLabs: sauceLabsConfig,
 
-    // start these browsers
-    // available browser launchers: https://npmjs.org/browse/keyword/karma-launcher
-    browsers: ['Chrome'],
+    // use an extended timeout for capturing Sauce Labs
+    // browsers in case the service is busy
+    captureTimeout: 3 * 60000,
 
+    customLaunchers: customLaunchers,
+
+    browsers: Object.keys(customLaunchers),
 
-    // Continuous Integration mode
-    // if true, Karma captures browsers, runs the tests and exits
     singleRun: false,
 
-    // Concurrency level
-    // how many browser should be started simultanous
     concurrency: Infinity
   })
-}
+};
diff --git a/karma-tests/wombat.spec.js b/karma-tests/wombat.spec.js
index a1b681af..7012da83 100644
--- a/karma-tests/wombat.spec.js
+++ b/karma-tests/wombat.spec.js
@@ -1,4 +1,5 @@
 var WOMBAT_SRC = '../pywb/static/wombat.js';
+var DEFAULT_TIMEOUT = 20000;
 
 // creates a new document in an <iframe> and runs
 // a WombatJS test case in it.
@@ -80,6 +81,8 @@ function runWombatTest(testCase, done) {
 }
 
 describe('WombatJS', function () {
+    this.timeout(DEFAULT_TIMEOUT);
+
     var wombatScript;
 
     before(function (done) {
diff --git a/package.json b/package.json
index a24da2a1..241a71ba 100644
--- a/package.json
+++ b/package.json
@@ -28,6 +28,7 @@
     "karma-firefox-launcher": "^0.1.7",
     "karma-html2js-preprocessor": "^0.1.0",
     "karma-mocha": "^0.2.1",
+    "karma-sauce-launcher": "^0.3.0",
     "mocha": "^2.3.4"
   }
 }