diff --git a/Gruntfile.js b/Gruntfile.js
new file mode 100644
index 0000000..21489be
--- /dev/null
+++ b/Gruntfile.js
@@ -0,0 +1,77 @@
+module.exports = function(grunt) {
+  'use strict';
+
+  // Project configuration.
+  grunt.initConfig({
+    pkg: grunt.file.readJSON('package.json'),
+
+    jshint: {
+      options: {
+        indent : 2,
+        maxlen : 80,
+        node : true,
+        eqeqeq : true,
+        latedef : true,
+        noarg : true,
+        noempty : true,
+        plusplus : true,
+        quotmark : true,
+        undef : true,
+        unused : true,
+        strict : true,
+        trailing : true
+      },
+
+      srcFiles : {
+        src : ['Gruntfile.js', 'index.js']
+      },
+
+      testFiles : {
+        options : {
+          expr : true,
+          globals : {
+            describe : true,
+            it : true,
+            after : true,
+            before : true,
+            afterEach : true,
+            beforeEach : true,
+            expect : true
+          }
+        },
+        src : ['test/parameters.js']
+      }
+    },
+
+    mochaTest: {
+      test: {
+        options: {
+          require : ['test/setup.js'],
+          reporter: 'dot',
+          ui: 'bdd',
+          ignoreLeaks: false
+        },
+        src: ['test/**/*.js']
+      }
+    }
+  });
+
+
+  // Load the jshint plugin
+  grunt.loadNpmTasks('grunt-contrib-jshint');
+
+  // Load the mocha runner plugin
+  grunt.loadNpmTasks('grunt-mocha-test');
+
+
+  // Test tasks
+  grunt.registerTask('test', [
+    'jshint:srcFiles',
+    'jshint:testFiles',
+    'mochaTest'
+  ]);
+
+  // Default task(s).
+  grunt.registerTask('default', ['test']);
+
+};
diff --git a/test/parameters.js b/test/parameters.js
new file mode 100644
index 0000000..90788b4
--- /dev/null
+++ b/test/parameters.js
@@ -0,0 +1,178 @@
+(function () {
+  'use strict';
+
+  var expect = require('chai').expect;
+  var sinon = require('sinon');
+
+  var parameters = require('../');
+
+
+  describe('parameters-middleware', function () {
+    it('is accessible', function () {
+      expect(parameters).to.be.defined;
+    });
+
+
+    it('is a function', function () {
+      expect(parameters).to.be.a('function');
+    });
+
+
+    it('throws an error if no params are specified', function () {
+      function withoutParams() {
+        parameters();
+      }
+
+      var message = 'Missconfigured: no required parameters set';
+      expect(withoutParams).to.throw(message);
+    });
+
+
+    it('returns a middleware', function () {
+      var middleware = parameters({
+        query : ['foo', 'bar']
+      });
+
+      expect(middleware).to.be.a('function');
+      expect(middleware).to.have.length(3);
+    });
+
+
+    describe('middleware', function () {
+      var req;
+      var res;
+      var next;
+
+      before(function () {
+        req = {
+          query : {
+            foo : 'foobar'
+          },
+          body : {
+            bar : 'barbaz'
+          },
+          custom : {
+            baz : 'bazfoo'
+          }
+        };
+
+        res = {
+          send : sinon.spy()
+        };
+
+        next = sinon.spy();
+      });
+
+
+      beforeEach(function () {
+        res.send.reset();
+        next.reset();
+      });
+
+
+      it('calls the next middleware if all parameters are set', function () {
+        var middleware = parameters({
+          query : ['foo'],
+          body : ['bar'],
+          custom : ['baz']
+        });
+
+        middleware(req, res, next);
+
+        expect(next).to.have.been.calledOnce;
+      });
+
+
+      it('does not call the next middleware if a param is missing',
+        function () {
+          var middleware = parameters({
+            query : ['missing']
+          });
+
+          middleware(req, res, next);
+
+          expect(next).not.to.have.been.called;
+        });
+
+
+      it('responds with a status 400 (bad request) if params are missing',
+        function () {
+          var middleware = parameters({
+            query : ['missing']
+          });
+
+          middleware(req, res, next);
+          expect(res.send).to.have.been.calledWith(400);
+        });
+
+
+      it('uses the configured message', function () {
+        var params = {
+          query : ['missing']
+        };
+
+        var options = {
+          message : 'Custom message'
+        };
+
+        var middleware = parameters(params, options);
+
+        middleware(req, res, next);
+
+        var message = res.send.lastCall.args[1];
+        expect(message).to.equal(options.message);
+      });
+
+
+      it('allows to use a message function', function () {
+        var params = {
+          query : ['missing']
+        };
+
+        var options = {
+          message : function (missing) {
+            return 'Missing params: ' + missing.join(', ');
+          }
+        };
+
+        var middleware = parameters(params, options);
+
+        middleware(req, res, next);
+
+        var message = res.send.lastCall.args[1];
+        var expected = 'Missing params: missing';
+        expect(message).to.equal(expected);
+      });
+
+
+      it('checks arbitrary properties in the request', function () {
+        var params = {
+          // Usually, there's no 'custom' property in the request object
+          custom : ['baz']
+        };
+
+        var middleware = parameters(params);
+
+        middleware(req, res, next);
+        expect(next).to.have.been.called;
+      });
+
+
+      it('respects the property in which each param should be found',
+        function () {
+          var params = {
+            // The request has 'foo' in the query and 'bar' in the body,
+            // this should fail...
+            query : ['bar'],
+            body : ['foo']
+          };
+
+          var middleware = parameters(params);
+
+          middleware(req, res, next);
+          expect(next).not.to.have.been.called;
+          expect(res.send).to.have.been.called;
+        });
+    }); // middleware
+  }); // parameters-middleware
+})();
diff --git a/test/setup.js b/test/setup.js
new file mode 100644
index 0000000..725d63f
--- /dev/null
+++ b/test/setup.js
@@ -0,0 +1,13 @@
+/**
+ * Setup code for the test environment.
+ */
+
+/** Sets sinon-related assertions into Chai's should and expect APIs. */
+(function () {
+  'use strict';
+
+  var chai = require('chai');
+  var sinonChai = require('sinon-chai');
+
+  chai.use(sinonChai);
+})();