diff --git a/Makefile b/Makefile
index 333086277d..37e887f9a4 100644
--- a/Makefile
+++ b/Makefile
@@ -21,6 +21,7 @@ mocha.js BUILDTMP/mocha.js: $(SRC) browser-entry.js
 	@printf "==> [Browser :: build]\n"
 	mkdir -p ${@D}
 	$(BROWSERIFY) ./browser-entry \
+		--require buffer/:buffer \
 		--plugin ./scripts/dedefine \
 		--ignore 'fs' \
 		--ignore 'glob' \
diff --git a/karma.conf.js b/karma.conf.js
index 21e1e68870..94e4a0e7d7 100644
--- a/karma.conf.js
+++ b/karma.conf.js
@@ -49,6 +49,7 @@ module.exports = function (config) {
           .ignore('fs')
           .ignore('path')
           .ignore('supports-color')
+          .require(path.join(__dirname, 'node_modules', 'buffer'), {expose: 'buffer'})
           .on('bundled', function (err, content) {
             if (!err && bundleDirpath) {
               // write bundle to directory for debugging
diff --git a/lib/utils.js b/lib/utils.js
index 046e097296..9bac5a8cf7 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -209,17 +209,6 @@ var isArray = typeof Array.isArray === 'function' ? Array.isArray : function (ob
 
 exports.isArray = isArray;
 
-/**
- * Buffer.prototype.toJSON polyfill.
- *
- * @type {Function}
- */
-if (typeof Buffer !== 'undefined' && Buffer.prototype) {
-  Buffer.prototype.toJSON = Buffer.prototype.toJSON || function () {
-    return Array.prototype.slice.call(this, 0);
-  };
-}
-
 /**
  * Ignored files.
  *
@@ -411,7 +400,7 @@ var type = exports.type = function type (value) {
     return 'undefined';
   } else if (value === null) {
     return 'null';
-  } else if (typeof Buffer !== 'undefined' && Buffer.isBuffer(value)) {
+  } else if (Buffer.isBuffer(value)) {
     return 'buffer';
   }
   return Object.prototype.toString.call(value)
@@ -439,7 +428,7 @@ exports.stringify = function (value) {
 
   if (!~indexOf(['object', 'array', 'function'], typeHint)) {
     if (typeHint === 'buffer') {
-      var json = value.toJSON();
+      var json = Buffer.prototype.toJSON.call(value);
       // Based on the toJSON result
       return jsonStringify(json.data && json.type ? json.data : json, 2)
         .replace(/,(\n|$)/g, '$1');
@@ -549,17 +538,6 @@ function jsonStringify (object, spaces, depth) {
     (str.length !== 1 ? '\n' + repeat(' ', --space) + end : end);
 }
 
-/**
- * Test if a value is a buffer.
- *
- * @api private
- * @param {*} value The value to test.
- * @return {boolean} True if `value` is a buffer, otherwise false
- */
-exports.isBuffer = function (value) {
-  return typeof Buffer !== 'undefined' && Buffer.isBuffer(value);
-};
-
 /**
  * Return a new Thing that has the keys in sorted order. Recursive.
  *
diff --git a/package.json b/package.json
index 3a603d37b2..63d87fe2b0 100644
--- a/package.json
+++ b/package.json
@@ -321,7 +321,8 @@
   "devDependencies": {
     "@coderbyheart/karma-sauce-launcher": "git://github.com/coderbyheart/karma-sauce-launcher#5259942cd6d40090eaa13ceeef5b0b8738c7710f",
     "assert": "^1.4.1",
-    "browserify": "^13.0.0",
+    "browserify": "^14.4.0",
+    "buffer": "^4.9.1",
     "coffee-script": "^1.10.0",
     "coveralls": "^2.11.15",
     "cross-spawn": "^5.1.0",
@@ -367,7 +368,8 @@
     "fs": false,
     "glob": false,
     "path": false,
-    "supports-color": false
+    "supports-color": false,
+    "buffer": "buffer"
   },
   "homepage": "https://mochajs.org",
   "logo": "https://cldup.com/S9uQ-cOLYz.svg"
diff --git a/test/unit/utils.spec.js b/test/unit/utils.spec.js
index 3f643ea27a..cb33a7c520 100644
--- a/test/unit/utils.spec.js
+++ b/test/unit/utils.spec.js
@@ -495,18 +495,6 @@ describe('lib/utils', function () {
     });
   });
 
-  describe('isBuffer()', function () {
-    var isBuffer = utils.isBuffer;
-    it('should test if object is a Buffer', function () {
-      expect(isBuffer(Buffer.from([0x01])))
-        .to
-        .equal(true);
-      expect(isBuffer({}))
-        .to
-        .equal(false);
-    });
-  });
-
   describe('map()', function () {
     var map = utils.map;
     it('should behave same as Array.prototype.map', function () {