diff --git conditional_styles.info conditional_styles.info
index 62322f9..1c2d835 100644
--- conditional_styles.info
+++ conditional_styles.info
@@ -5,3 +5,4 @@ core = 7.x
 
 files[] = conditional_styles.install
 files[] = conditional_styles.module
+files[] = tests/conditional_styles_test.test
diff --git tests/conditional_styles.test tests/conditional_styles.test
new file mode 100644
index 0000000..6d60e73
--- /dev/null
+++ tests/conditional_styles.test
@@ -0,0 +1,24 @@
+<?php
+/**
+ * @file
+ * Tests for conditional stylesheets.
+ */
+
+/**
+ * Test the Conditional Stylesheets module.
+ */
+class ConditionalStylesheetsTestCase extends DrupalWebTestCase {
+  public static function getInfo() {
+    return array(
+      'name' => 'Conditional stylesheets',
+      'description' => 'Tests adding various cascading stylesheets to the page.',
+      'group' => 'Conditional Stylesheets',
+    );
+  }
+
+  function setUp() {
+    parent::setUp('conditional_stylesheets_test');
+    theme_enable(array('test_theme'));
+  }
+
+}
diff --git tests/conditional_styles_test.info tests/conditional_styles_test.info
new file mode 100644
index 0000000..94fd1ec
--- /dev/null
+++ tests/conditional_styles_test.info
@@ -0,0 +1,8 @@
+name = "Conditional Stylesheets Tests"
+package = Testing
+
+core = 7.x
+hidden = TRUE
+dependencies[] = conditional_styles
+
+files[] = conditional_styles_test.module
diff --git tests/conditional_styles_test.module tests/conditional_styles_test.module
new file mode 100644
index 0000000..5519c4d
--- /dev/null
+++ tests/conditional_styles_test.module
@@ -0,0 +1,16 @@
+<?php
+/**
+ * @file
+ * Test module for conditional stylesheets.
+ */
+
+/**
+ * Implements hook_system_info_alter().
+ */
+function conditional_styles_test_system_info_alter(&$info, $file, $type) {
+  // @todo Hack the conditional_theme into the system somehow, or wait until
+  // core provides support for testing themes provided by modules.
+  if ($type == 'theme' && $file->name == 'test_theme') {
+    $info['stylesheets-conditional']['gte IE 1']['all'][] = '../../../modules/simpletest/tests/common_test.css';
+  }
+}
diff --git tests/conditional_theme/conditional_theme.conditional.css tests/conditional_theme/conditional_theme.conditional.css
new file mode 100644
index 0000000..7f52b38
--- /dev/null
+++ tests/conditional_theme/conditional_theme.conditional.css
@@ -0,0 +1 @@
+/* This file is for testing CSS file inclusion, no contents are necessary. */
diff --git tests/conditional_theme/conditional_theme.info tests/conditional_theme/conditional_theme.info
new file mode 100644
index 0000000..55eb522
--- /dev/null
+++ tests/conditional_theme/conditional_theme.info
@@ -0,0 +1,11 @@
+; This theme is not actually used by the test framework. See
+; conditional_styles_test_system_info_alter() for the dirty truth.
+
+name = Conditional Test theme
+description = Theme for Conditional Stylesheets module
+
+core = 7.x
+engine = phptemplate
+hidden = TRUE
+
+stylesheets-conditional[gte IE 1][all][] = conditional-theme.conditional.css