diff --git a/lib/context.js b/lib/context.js
index 8151258..48c5f71 100644
--- a/lib/context.js
+++ b/lib/context.js
@@ -3,6 +3,8 @@
  * Module dependencies.
  */
 
+var createError = require('http-errors');
+var httpAssert = require('http-assert');
 var delegate = require('delegates');
 var assert = require('assert');
 var http = require('http');
@@ -49,6 +51,21 @@ var proto = module.exports = {
     }
   },
 
+  /**
+   * Similar to .throw(), adds assertion.
+   *
+   *    this.assert(this.user, 401, 'Please login!');
+   *
+   * See: https://github.com/jshttp/http-assert
+   *
+   * @param {Mixed} test
+   * @param {Number} status
+   * @param {String} message
+   * @api public
+   */
+
+  assert: httpAssert,
+
   /**
    * Throw an error with `msg` and optional `status`
    * defaulting to 500. Note that these are user-level
@@ -61,31 +78,16 @@ var proto = module.exports = {
    *    this.throw(new Error('invalid'), 400);
    *    this.throw(400, new Error('invalid'));
    *
+   * See: https://github.com/jshttp/http-errors
+   *
    * @param {String|Number|Error} err, msg or status
    * @param {String|Number|Error} [err, msg or status]
    * @param {Object} [props]
    * @api public
    */
 
-  throw: function(msg, status, props){
-    if ('object' == typeof status && !(status instanceof Error)) {
-      props = status;
-      status = null;
-    }
-
-    if ('number' == typeof msg) {
-      var tmp = msg;
-      msg = status || http.STATUS_CODES[tmp];
-      status = tmp;
-    }
-
-    props = props || {};
-
-    var err = msg instanceof Error ? msg : new Error(msg);
-    for (var key in props) err[key] = props[key];
-    err.status = status || err.status || 500;
-    err.expose = 'number' == typeof err.status && http.STATUS_CODES[err.status] && err.status < 500;
-    throw err;
+  throw: function(){
+    throw createError.apply(null, arguments);
   },
 
   /**
diff --git a/package.json b/package.json
index 1c8c172..def1965 100644
--- a/package.json
+++ b/package.json
@@ -18,26 +18,28 @@
   ],
   "license": "MIT",
   "dependencies": {
-    "escape-html": "~1.0.1",
-    "statuses": "~1.0.1",
     "accepts": "~1.1.0",
-    "type-is": "~1.5.0",
-    "mime-types": "~2.0.0",
-    "media-typer": "~0.3.0",
-    "on-finished": "~2.1.0",
     "co": "~3.1.0",
     "content-disposition": "~0.1.0",
-    "debug": "*",
-    "fresh": "~0.2.1",
-    "koa-compose": "~2.3.0",
-    "koa-is-json": "~1.0.0",
     "cookies": "~0.5.0",
+    "debug": "*",
     "delegates": "0.0.3",
     "destroy": "~1.0.3",
     "error-inject": "~1.0.0",
-    "vary": "~1.0.0",
+    "escape-html": "~1.0.1",
+    "fresh": "~0.2.1",
+    "http-assert": "~1.0.1",
+    "http-errors": "~1.2.0",
+    "koa-compose": "~2.3.0",
+    "koa-is-json": "~1.0.0",
+    "media-typer": "~0.3.0",
+    "mime-types": "~2.0.0",
+    "on-finished": "~2.1.0",
+    "only": "0.0.2",
     "parseurl": "~1.3.0",
-    "only": "0.0.2"
+    "statuses": "~1.0.1",
+    "type-is": "~1.5.0",
+    "vary": "~1.0.0"
   },
   "devDependencies": {
     "istanbul-harmony": "~0.3.0",
diff --git a/test/context/assert.js b/test/context/assert.js
new file mode 100644
index 0000000..04a7980
--- /dev/null
+++ b/test/context/assert.js
@@ -0,0 +1,17 @@
+
+var context = require('../context');
+var assert = require('assert');
+
+describe('ctx.assert(value, status)', function(){
+  it('should throw an error', function(){
+    var ctx = context();
+
+    try {
+      ctx.assert(false, 404);
+      throw new Error('asdf');
+    } catch (err) {
+      assert(404 == err.status);
+      assert(err.expose);
+    }
+  })
+})