diff --git a/library/HTMLPurifier.includes.php b/library/HTMLPurifier.includes.php
index 7f78c017..27094120 100644
--- a/library/HTMLPurifier.includes.php
+++ b/library/HTMLPurifier.includes.php
@@ -129,8 +129,8 @@ require 'HTMLPurifier/ConfigSchema/StringHash.php';
 require 'HTMLPurifier/ConfigSchema/StringHashAdapter.php';
 require 'HTMLPurifier/ConfigSchema/StringHashParser.php';
 require 'HTMLPurifier/ConfigSchema/StringHashReverseAdapter.php';
-require 'HTMLPurifier/ConfigSchema/Interchange/Validator.php';
-require 'HTMLPurifier/ConfigSchema/Interchange/Validator/IdExists.php';
+require 'HTMLPurifier/ConfigSchema/Validator.php';
+require 'HTMLPurifier/ConfigSchema/Validator/IdExists.php';
 require 'HTMLPurifier/DefinitionCache/Decorator.php';
 require 'HTMLPurifier/DefinitionCache/Null.php';
 require 'HTMLPurifier/DefinitionCache/Serializer.php';
diff --git a/library/HTMLPurifier/ConfigSchema/Interchange.php b/library/HTMLPurifier/ConfigSchema/Interchange.php
index 5bfe1128..47c1ce5a 100644
--- a/library/HTMLPurifier/ConfigSchema/Interchange.php
+++ b/library/HTMLPurifier/ConfigSchema/Interchange.php
@@ -11,7 +11,7 @@ class HTMLPurifier_ConfigSchema_Interchange
     /**
      * Hash table of allowed types.
      */
-    protected $types = array(
+    private $types = array(
         'string'    => 'String',
         'istring'   => 'Case-insensitive string',
         'text'      => 'Text',
@@ -28,12 +28,12 @@ class HTMLPurifier_ConfigSchema_Interchange
     /**
      * Array of Namespace ID => array(namespace info)
      */
-    protected $namespaces;
+    private $namespaces;
     
     /**
      * Array of Directive ID => array(directive info)
      */
-    protected $directives;
+    private $directives;
     
     /** Get all namespaces */
     public function getNamespaces() {return $this->namespaces;}
@@ -71,9 +71,7 @@ class HTMLPurifier_ConfigSchema_Interchange
      * to be used for data-input.
      */
     public function getValidatorAdapter() {
-        return
-            new HTMLPurifier_ConfigSchema_Interchange_Validator_IdExists(
-            $this);
+        
     }
     
 }
diff --git a/library/HTMLPurifier/ConfigSchema/Interchange/Validator.php b/library/HTMLPurifier/ConfigSchema/Interchange/Validator.php
deleted file mode 100644
index fae8557d..00000000
--- a/library/HTMLPurifier/ConfigSchema/Interchange/Validator.php
+++ /dev/null
@@ -1,43 +0,0 @@
-<?php
-
-/**
- * Base decorator class for HTMLPurifier_ConfigSchema_Interchange
- */
-class HTMLPurifier_ConfigSchema_Interchange_Validator extends HTMLPurifier_ConfigSchema_Interchange
-{
-    /**
-     * Interchange object this schema is wrapping.
-     */
-    protected $interchange;
-    
-    /** @param Object to decorate */
-    public function __construct($i = null) {
-        $this->decorate($i);
-    }
-    
-    /** Wrap this decorator around an object. */
-    public function decorate($i) {
-        $this->interchange =  $i;
-    }
-    
-    public function getNamespaces() {
-        return $this->interchange->getNamespaces();
-    }
-    
-    public function getDirectives() {
-        return $this->interchange->getDirectives();
-    }
-    
-    public function getTypes() {
-        return $this->interchange->getTypes();
-    }
-    
-    public function addNamespace($arr) {
-        $this->interchange->addNamespace($arr);
-    }
-    
-    public function addDirective($arr) {
-        $this->interchange->addNamespace($arr);
-    }
-    
-}
diff --git a/library/HTMLPurifier/ConfigSchema/Interchange/Validator/IdExists.php b/library/HTMLPurifier/ConfigSchema/Interchange/Validator/IdExists.php
deleted file mode 100644
index 23153242..00000000
--- a/library/HTMLPurifier/ConfigSchema/Interchange/Validator/IdExists.php
+++ /dev/null
@@ -1,20 +0,0 @@
-<?php
-
-class HTMLPurifier_ConfigSchema_Interchange_Validator_IdExists extends HTMLPurifier_ConfigSchema_Interchange_Validator
-{
-    
-    public function addNamespace($arr) {
-        if (!isset($arr['ID'])) {
-            throw new HTMLPurifier_ConfigSchema_Exception('Namespace must have ID');
-        }
-        parent::addNamespace($arr);
-    }
-    
-    public function addDirective($arr) {
-        if (!isset($arr['ID'])) {
-            throw new HTMLPurifier_ConfigSchema_Exception('Directive must have ID');
-        }
-        parent::addDirective($arr);
-    }
-    
-}
diff --git a/library/HTMLPurifier/ConfigSchema/Validator.php b/library/HTMLPurifier/ConfigSchema/Validator.php
new file mode 100644
index 00000000..e87302a0
--- /dev/null
+++ b/library/HTMLPurifier/ConfigSchema/Validator.php
@@ -0,0 +1,39 @@
+<?php
+
+/**
+ * Base validator for HTMLPurifier_ConfigSchema_Interchange
+ */
+class HTMLPurifier_ConfigSchema_Validator
+{
+    
+    /**
+     * Validates and filters a namespace.
+     */
+    public function validateNamespace(&$arr, $interchange) {
+        $this->validate($arr, $interchange, 'namespace');
+    }
+    
+    /**
+     * Validates and filters a directive.
+     */
+    public function validateDirective(&$arr, $interchange) {
+        $this->validate($arr, $interchange, 'directive');
+    }
+    
+    /**
+     * Common validator, throwing an exception on error. It can
+     * also performing filtering or evaluation functions.
+     *
+     * @note This is strictly for convenience reasons when subclasing.
+     * 
+     * @param $arr Array to validate.
+     * @param $interchange HTMLPurifier_ConfigSchema_Interchange object
+     *      that is being processed.
+     * @param $type Type of object being validated, this saves a little work
+     *      if only cosmetic changes are being made between namespaces
+     *      and directives.
+     */
+    protected function validate(&$arr, $interchange, $type) {}
+    
+    
+}
diff --git a/library/HTMLPurifier/ConfigSchema/Validator/IdExists.php b/library/HTMLPurifier/ConfigSchema/Validator/IdExists.php
new file mode 100644
index 00000000..2b12d2de
--- /dev/null
+++ b/library/HTMLPurifier/ConfigSchema/Validator/IdExists.php
@@ -0,0 +1,15 @@
+<?php
+
+/**
+ * Validates that an ID field exists in the array
+ */
+class HTMLPurifier_ConfigSchema_Validator_IdExists extends HTMLPurifier_ConfigSchema_Validator
+{
+    
+    public function validate(&$arr, $interchange, $type) {
+        if (!isset($arr['ID'])) {
+            throw new HTMLPurifier_ConfigSchema_Exception('ID must exist in ' . $type);
+        }
+    }
+    
+}
diff --git a/maintenance/flush.php b/maintenance/flush.php
index 5cf5e88b..914be8bd 100644
--- a/maintenance/flush.php
+++ b/maintenance/flush.php
@@ -17,7 +17,7 @@ function e($cmd) {
     echo "\n";
 }
 
-e('php flush-definition-cache.php');
 e('php generate-includes.php');
+e('php flush-definition-cache.php');
 e('php generate-schema-cache.php');
 e('php generate-standalone.php');
diff --git a/tests/HTMLPurifier/ConfigSchema/Interchange/Validator/IdExistsTest.php b/tests/HTMLPurifier/ConfigSchema/Interchange/Validator/IdExistsTest.php
deleted file mode 100644
index ad506ce1..00000000
--- a/tests/HTMLPurifier/ConfigSchema/Interchange/Validator/IdExistsTest.php
+++ /dev/null
@@ -1,23 +0,0 @@
-<?php
-
-class HTMLPurifier_ConfigSchema_Interchange_Validator_IdExistsTest extends HTMLPurifier_ConfigSchema_Interchange_ValidatorHarness
-{
-    
-    public function setup() {
-        parent::setup();
-        $this->validator = new HTMLPurifier_ConfigSchema_Interchange_Validator_IdExists($this->mock);
-    }
-    
-    public function testNamespace() {
-        $this->mock->expectNever('addNamespace');
-        $this->expectSchemaException('Namespace must have ID');
-        $this->validator->addNamespace();
-    }
-    
-    public function testDirective() {
-        $this->mock->expectNever('addDirective');
-        $this->expectSchemaException('Directive must have ID');
-        $this->validator->addDirective();
-    }
-    
-}
diff --git a/tests/HTMLPurifier/ConfigSchema/Validator/IdExistsTest.php b/tests/HTMLPurifier/ConfigSchema/Validator/IdExistsTest.php
new file mode 100644
index 00000000..6a42e1ed
--- /dev/null
+++ b/tests/HTMLPurifier/ConfigSchema/Validator/IdExistsTest.php
@@ -0,0 +1,23 @@
+<?php
+
+class HTMLPurifier_ConfigSchema_Validator_IdExistsTest extends HTMLPurifier_ConfigSchema_ValidatorHarness
+{
+    
+    public function setup() {
+        parent::setup();
+        $this->validator = new HTMLPurifier_ConfigSchema_Validator_IdExists();
+    }
+    
+    public function testValidateNamespace() {
+        $this->expectSchemaException('ID must exist in namespace');
+        $arr = array();
+        $this->validator->validateNamespace($arr, $this->interchange);
+    }
+    
+    public function testValidateDirective() {
+        $this->expectSchemaException('ID must exist in directive');
+        $arr = array();
+        $this->validator->validateDirective($arr, $this->interchange);
+    }
+    
+}
diff --git a/tests/HTMLPurifier/ConfigSchema/Interchange/ValidatorHarness.php b/tests/HTMLPurifier/ConfigSchema/ValidatorHarness.php
similarity index 57%
rename from tests/HTMLPurifier/ConfigSchema/Interchange/ValidatorHarness.php
rename to tests/HTMLPurifier/ConfigSchema/ValidatorHarness.php
index 204a8c0a..9230e20a 100644
--- a/tests/HTMLPurifier/ConfigSchema/Interchange/ValidatorHarness.php
+++ b/tests/HTMLPurifier/ConfigSchema/ValidatorHarness.php
@@ -1,14 +1,13 @@
 <?php
 
-class HTMLPurifier_ConfigSchema_Interchange_ValidatorHarness extends UnitTestCase
+class HTMLPurifier_ConfigSchema_ValidatorHarness extends UnitTestCase
 {
     
-    protected $validator;
-    protected $mock;
+    protected $interchange, $validator;
     
     public function setup() {
         generate_mock_once('HTMLPurifier_ConfigSchema_Interchange');
-        $this->mock = new HTMLPurifier_ConfigSchema_InterchangeMock();
+        $this->interchange = new HTMLPurifier_ConfigSchema_InterchangeMock();
     }
     
     protected function expectSchemaException($msg) {