diff --git a/lib/PHPParser/Builder/Interface.php b/lib/PHPParser/Builder/Interface.php
new file mode 100644
index 0000000..8c76dc9
--- /dev/null
+++ b/lib/PHPParser/Builder/Interface.php
@@ -0,0 +1,92 @@
+<?php
+
+class PHPParser_Builder_Interface extends PHPParser_BuilderAbstract
+{
+    protected $name;
+    protected $extends;
+    protected $constants;
+    protected $methods;
+
+    /**
+     * Creates an interface builder.
+     *
+     * @param string $name Name of the interface
+     */
+    public function __construct($name) {
+        $this->name = $name;
+        $this->extends = array();
+        $this->constants = $this->methods = array();
+    }
+
+    /**
+     * Extends one or more interfaces.
+     *
+     * @param PHPParser_Node_Name|string $interface Name of interface to extend
+     * @param PHPParser_Node_Name|string $...       More interfaces to extend
+     *
+     * @return PHPParser_Builder_Interface The builder instance (for fluid interface)
+     */
+    public function extend() {
+        foreach (func_get_args() as $interface) {
+            $this->extends[] = $this->normalizeName($interface);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Adds a statement.
+     *
+     * @param PHPParser_Node_Stmt|PHPParser_Builder $stmt The statement to add
+     *
+     * @return PHPParser_Builder_Interface The builder instance (for fluid interface)
+     */
+    public function addStmt($stmt) {
+        $stmt = $this->normalizeNode($stmt);
+
+        $type = $stmt->getType();
+        switch ($type) {
+            case 'Stmt_ClassConst':
+                $this->constants[] = $stmt;
+                break;
+
+            case 'Stmt_ClassMethod':
+                // we erase all statements in the body of an interface method
+                $stmt->stmts = null;
+                $this->methods[] = $stmt;
+                break;
+
+            default:
+                throw new LogicException(sprintf('Unexpected node of type "%s"', $type));
+        }
+
+        return $this;
+    }
+
+    /**
+     * Adds multiple statements.
+     *
+     * @param array $stmts The statements to add
+     *
+     * @return PHPParser_Builder_Class The builder instance (for fluid interface)
+     */
+    public function addStmts(array $stmts) {
+        foreach ($stmts as $stmt) {
+            $this->addStmt($stmt);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Returns the built class node.
+     *
+     * @return PHPParser_Node_Stmt_Interface The built interface node
+     */
+    public function getNode() {
+        return new PHPParser_Node_Stmt_Interface($this->name, array(
+            'extends' => $this->extends,
+            'stmts' => array_merge($this->constants, $this->methods),
+        ));
+    }
+}
\ No newline at end of file
diff --git a/lib/PHPParser/BuilderFactory.php b/lib/PHPParser/BuilderFactory.php
index 2212dd8..48941dc 100644
--- a/lib/PHPParser/BuilderFactory.php
+++ b/lib/PHPParser/BuilderFactory.php
@@ -1,12 +1,13 @@
 <?php
 
 /**
- * "class" and "function" are reserved keywords, so the methods are defined as _class()
- * and _function() in the class and are made available as class() and function() through
- * __call() magic.
+ * "class", "interface" and "function" are reserved keywords, so the methods are defined as _class(),
+ * _interface() and _function() in the class and are made available as class(), interface() and function()
+ * through __call() magic.
  *
- * @method PHPParser_Builder_Class    class(string $name)    Creates a class builder.
- * @method PHPParser_Builder_Function function(string $name) Creates a function builder
+ * @method PHPParser_Builder_Class     class(string $name)     Creates a class builder.
+ * @method PHPParser_Builder_Function  function(string $name)  Creates a function builder
+ * @method PHPParser_Builder_Interface interface(string $name) Creates an interface builder.
  */
 class PHPParser_BuilderFactory
 {
@@ -21,6 +22,17 @@ class PHPParser_BuilderFactory
         return new PHPParser_Builder_Class($name);
     }
 
+    /**
+     * Creates a interface builder.
+     *
+     * @param string $name Name of the interface
+     *
+     * @return PHPParser_Builder_Class The created interface builder
+     */
+    protected function _interface($name) {
+        return new PHPParser_Builder_Interface($name);
+    }
+
     /**
      * Creates a method builder.
      *
@@ -66,10 +78,8 @@ class PHPParser_BuilderFactory
     }
 
     public function __call($name, array $args) {
-        if ('class' === $name) {
-            return call_user_func_array(array($this, '_class'), $args);
-        } elseif ('function' === $name) {
-            return call_user_func_array(array($this, '_function'), $args);
+        if (method_exists($this, '_' . $name)) {
+            return call_user_func_array(array($this, '_' . $name), $args);
         }
 
         throw new LogicException(sprintf('Method "%s" does not exist', $name));
diff --git a/test/PHPParser/Tests/Builder/InterfaceTest.php b/test/PHPParser/Tests/Builder/InterfaceTest.php
new file mode 100644
index 0000000..fb36338
--- /dev/null
+++ b/test/PHPParser/Tests/Builder/InterfaceTest.php
@@ -0,0 +1,91 @@
+<?php
+
+/**
+ * This class unit-tests the interface builder
+ */
+class PHPParser_Tests_Builder_InterfaceTest extends PHPUnit_Framework_TestCase
+{
+    /** @var PHPParser_Builder_Interface */
+    protected $builder;
+
+    protected function setUp() {
+        $this->builder = new PHPParser_Builder_Interface('Contract');
+    }
+
+    private function dump($node) {
+        $pp = new PHPParser_PrettyPrinter_Default();
+        return $pp->prettyPrint(array($node));
+    }
+
+    public function testEmpty() {
+        $contract = $this->builder->getNode();
+        $this->assertInstanceOf('PHPParser_Node_Stmt_Interface', $contract);
+        $this->assertEquals('Contract', $contract->name);
+    }
+
+    public function testExtending() {
+        $contract = $this->builder->extend('Space\Root1', 'Root2')->getNode();
+        $this->assertEquals(
+            new PHPParser_Node_Stmt_Interface('Contract', array(
+                'extends' => array(
+                    new PHPParser_Node_Name('Space\Root1'),
+                    new PHPParser_Node_Name('Root2')
+                ),
+            )), $contract
+        );
+    }
+
+    public function testAddMethod() {
+        $method = new PHPParser_Node_Stmt_ClassMethod('doSomething');
+        $contract = $this->builder->addStmt($method)->getNode();
+        $this->assertEquals(array($method), $contract->stmts);
+    }
+
+    public function testAddConst() {
+        $const = new PHPParser_Node_Stmt_ClassConst(array(
+            new PHPParser_Node_Const('SPEED_OF_LIGHT', new PHPParser_Node_Scalar_DNumber(299792458))
+        ));
+        $contract = $this->builder->addStmt($const)->getNode();
+        $this->assertEquals(299792458, $contract->stmts[0]->consts[0]->value->value);
+    }
+
+    public function testOrder() {
+        $const = new PHPParser_Node_Stmt_ClassConst(array(
+            new PHPParser_Node_Const('SPEED_OF_LIGHT', new PHPParser_Node_Scalar_DNumber(299792458))
+        ));
+        $method = new PHPParser_Node_Stmt_ClassMethod('doSomething');
+        $contract = $this->builder
+            ->addStmt($method)
+            ->addStmt($const)
+            ->getNode()
+        ;
+
+        $this->assertInstanceOf('PHPParser_Node_Stmt_ClassConst', $contract->stmts[0]);
+        $this->assertInstanceOf('PHPParser_Node_Stmt_ClassMethod', $contract->stmts[1]);
+    }
+
+    /**
+     * @expectedException LogicException
+     * @expectedExceptionMessage Unexpected node of type "Stmt_PropertyProperty"
+     */
+    public function testInvalidStmtError() {
+        $this->builder->addStmt(new PHPParser_Node_Stmt_PropertyProperty('invalid'));
+    }
+
+    public function testFullFunctional() {
+        $const = new PHPParser_Node_Stmt_ClassConst(array(
+            new PHPParser_Node_Const('SPEED_OF_LIGHT', new PHPParser_Node_Scalar_DNumber(299792458))
+        ));
+        $method = new PHPParser_Node_Stmt_ClassMethod('doSomething');
+        $contract = $this->builder
+            ->addStmt($method)
+            ->addStmt($const)
+            ->getNode()
+        ;
+
+        eval($this->dump($contract));
+
+        $this->assertTrue(interface_exists('Contract', false));
+    }
+}
+
diff --git a/test/PHPParser/Tests/BuilderFactoryTest.php b/test/PHPParser/Tests/BuilderFactoryTest.php
index c0d5501..0eaf8a9 100644
--- a/test/PHPParser/Tests/BuilderFactoryTest.php
+++ b/test/PHPParser/Tests/BuilderFactoryTest.php
@@ -2,28 +2,22 @@
 
 class PHPParser_Tests_BuilderFactoryTest extends PHPUnit_Framework_TestCase
 {
-    public function testCreateClassBuilder() {
+    /**
+     * @dataProvider provideTestFactory
+     */
+    public function testFactory($methodName, $className) {
         $factory = new PHPParser_BuilderFactory;
-        $this->assertInstanceOf('PHPParser_Builder_Class', $factory->class('Test'));
+        $this->assertInstanceOf($className, $factory->$methodName('test'));
     }
 
-    public function testCreateMethodBuilder() {
-        $factory = new PHPParser_BuilderFactory;
-        $this->assertInstanceOf('PHPParser_Builder_Method', $factory->method('test'));
-    }
-
-    public function testCreateParamBuilder() {
-        $factory = new PHPParser_BuilderFactory;
-        $this->assertInstanceOf('PHPParser_Builder_Param', $factory->param('test'));
-    }
-
-    public function testCreatePropertyBuilder() {
-        $factory = new PHPParser_BuilderFactory;
-        $this->assertInstanceOf('PHPParser_Builder_Property', $factory->property('test'));
-    }
-
-    public function testCreateFunctionBuilder() {
-        $factory = new PHPParser_BuilderFactory;
-        $this->assertInstanceOf('PHPParser_Builder_Function', $factory->function('test'));
+    public function provideTestFactory() {
+        return array(
+            array('class',     'PHPParser_Builder_Class'),
+            array('interface', 'PHPParser_Builder_Interface'),
+            array('method',    'PHPParser_Builder_Method'),
+            array('function',  'PHPParser_Builder_Function'),
+            array('property',  'PHPParser_Builder_Property'),
+            array('param',     'PHPParser_Builder_Param'),
+        );
     }
 }
\ No newline at end of file