diff --git a/amp.php b/amp.php
index 449a814ddc9..e84f62c5f5f 100644
--- a/amp.php
+++ b/amp.php
@@ -71,6 +71,7 @@ function amp_after_setup_theme() {
 	}
 
 	add_action( 'init', 'amp_init' );
+	add_action( 'widgets_init', 'AMP_Theme_Support::register_widgets' );
 	add_action( 'admin_init', 'AMP_Options_Manager::register_settings' );
 	add_filter( 'amp_post_template_analytics', 'amp_add_custom_analytics' );
 	add_action( 'wp_loaded', 'amp_post_meta_box' );
diff --git a/bin/add-test-widgets-to-sidebar.php b/bin/add-test-widgets-to-sidebar.php
index b84313a6e29..bd3a9e30d61 100644
--- a/bin/add-test-widgets-to-sidebar.php
+++ b/bin/add-test-widgets-to-sidebar.php
@@ -385,7 +385,15 @@ function amp_create_widget( $widget ) {
 		$title             = str_replace( '-', ' ', $title );
 		$settings['title'] = sprintf( 'Test %s Widget', ucwords( $title ) );
 	}
-	$widgets[] = $settings;
+
+	$number = 1;
+	unset( $widgets['_multiwidget'] );
+	if ( ! empty( $widgets ) ) {
+		$number = max( array_keys( $widgets ) );
+		$number = max( 1, $number );
+	}
+	$number++;
+	$widgets[ $number ] = $settings;
 	update_option( $option_key, $widgets );
 }
 
diff --git a/includes/class-amp-autoloader.php b/includes/class-amp-autoloader.php
index 1376d157e48..37264085486 100644
--- a/includes/class-amp-autoloader.php
+++ b/includes/class-amp-autoloader.php
@@ -79,6 +79,9 @@ class AMP_Autoloader {
 		'AMP_Image_Dimension_Extractor'               => 'includes/utils/class-amp-image-dimension-extractor',
 		'AMP_String_Utils'                            => 'includes/utils/class-amp-string-utils',
 		'AMP_WP_Utils'                                => 'includes/utils/class-amp-wp-utils',
+		'AMP_Widget_Archives'                         => 'includes/widgets/class-amp-widget-archives',
+		'AMP_Widget_Categories'                       => 'includes/widgets/class-amp-widget-categories',
+		'AMP_Widget_Recent_Comments'                  => 'includes/widgets/class-amp-widget-recent-comments',
 		'WPCOM_AMP_Polldaddy_Embed'                   => 'wpcom/class-amp-polldaddy-embed',
 		'AMP_Test_Stub_Sanitizer'                     => 'tests/stubs',
 		'AMP_Test_World_Sanitizer'                    => 'tests/stubs',
diff --git a/includes/class-amp-theme-support.php b/includes/class-amp-theme-support.php
index f7401cd9700..c85bdd9f941 100644
--- a/includes/class-amp-theme-support.php
+++ b/includes/class-amp-theme-support.php
@@ -196,6 +196,29 @@ public static function register_hooks() {
 		// @todo Add character conversion.
 	}
 
+	/**
+	 * Register/override widgets.
+	 *
+	 * @global WP_Widget_Factory
+	 * @return void
+	 */
+	public static function register_widgets() {
+		global $wp_widget_factory;
+		foreach ( $wp_widget_factory->widgets as $registered_widget ) {
+			$registered_widget_class_name = get_class( $registered_widget );
+			if ( ! preg_match( '/^WP_Widget_(.+)$/', $registered_widget_class_name, $matches ) ) {
+				continue;
+			}
+			$amp_class_name = 'AMP_Widget_' . $matches[1];
+			if ( ! class_exists( $amp_class_name ) || is_a( $amp_class_name, $registered_widget_class_name ) ) {
+				continue;
+			}
+
+			unregister_widget( $registered_widget_class_name );
+			register_widget( $amp_class_name );
+		}
+	}
+
 	/**
 	 * Override $wp_styles as AMP_WP_Styles, ideally before first instantiated as WP_Styles.
 	 *
@@ -463,7 +486,7 @@ public static function get_amp_component_scripts() {
 		 *
 		 * @since 0.7
 		 *
-		 * @param string $amp_scripts AMP Component scripts, mapping component names to component source URLs.
+		 * @param array $amp_scripts AMP Component scripts, mapping component names to component source URLs.
 		 */
 		$amp_scripts = apply_filters( 'amp_component_scripts', $amp_scripts );
 
diff --git a/includes/widgets/class-amp-widget-archives.php b/includes/widgets/class-amp-widget-archives.php
new file mode 100644
index 00000000000..0bad7cc33ea
--- /dev/null
+++ b/includes/widgets/class-amp-widget-archives.php
@@ -0,0 +1,103 @@
+<?php
+/**
+ * Class AMP_Widget_Archives
+ *
+ * @since 0.7.0
+ * @package AMP
+ */
+
+/**
+ * Class AMP_Widget_Archives
+ *
+ * @since 0.7.0
+ * @package AMP
+ */
+class AMP_Widget_Archives extends WP_Widget_Archives {
+
+	/**
+	 * Echoes the markup of the widget.
+	 *
+	 * Mainly copied from WP_Widget_Archives::widget()
+	 * Changes include:
+	 * An id for the <form>.
+	 * More escaping.
+	 * The dropdown is now filtered with 'wp_dropdown_cats.'
+	 * This enables adding an 'on' attribute, with the id of the form.
+	 * So changing the dropdown value will redirect to the category page, with valid AMP.
+	 *
+	 * @since 0.7.0
+	 *
+	 * @param array $args Widget display data.
+	 * @param array $instance Data for widget.
+	 * @return void.
+	 */
+	public function widget( $args, $instance ) {
+		if ( ! is_amp_endpoint() ) {
+			parent::widget( $args, $instance );
+			return;
+		}
+
+		$c = ! empty( $instance['count'] ) ? '1' : '0';
+		$d = ! empty( $instance['dropdown'] ) ? '1' : '0';
+
+		/** This filter is documented in wp-includes/widgets/class-wp-widget-pages.php */
+		$title = apply_filters( 'widget_title', empty( $instance['title'] ) ? __( 'Archives', 'default' ) : $instance['title'], $instance, $this->id_base );
+		echo wp_kses_post( $args['before_widget'] );
+		if ( $title ) :
+			echo wp_kses_post( $args['before_title'] . $title . $args['after_title'] );
+		endif;
+
+		if ( $d ) :
+			$dropdown_id = "{$this->id_base}-dropdown-{$this->number}";
+			?>
+			<form action="<?php echo esc_url( home_url() ); ?>" method="get" target="_top">
+				<label class="screen-reader-text" for="<?php echo esc_attr( $dropdown_id ); ?>"><?php echo esc_html( $title ); ?></label>
+				<select id="<?php echo esc_attr( $dropdown_id ); ?>" name="archive-dropdown" on="change:AMP.navigateTo(url=event.value)">
+					<?php
+
+					/** This filter is documented in wp-includes/widgets/class-wp-widget-archives.php */
+					$dropdown_args = apply_filters( 'widget_archives_dropdown_args', array(
+						'type'            => 'monthly',
+						'format'          => 'option',
+						'show_post_count' => $c,
+					) );
+
+					switch ( $dropdown_args['type'] ) {
+						case 'yearly':
+							$label = __( 'Select Year', 'default' );
+							break;
+						case 'monthly':
+							$label = __( 'Select Month', 'default' );
+							break;
+						case 'daily':
+							$label = __( 'Select Day', 'default' );
+							break;
+						case 'weekly':
+							$label = __( 'Select Week', 'default' );
+							break;
+						default:
+							$label = __( 'Select Post', 'default' );
+							break;
+					}
+					?>
+					<option value=""><?php echo esc_attr( $label ); ?></option>
+					<?php wp_get_archives( $dropdown_args ); ?>
+				</select>
+			</form>
+		<?php else : ?>
+			<ul>
+				<?php
+
+				/** This filter is documented in wp-includes/widgets/class-wp-widget-archives.php */
+				wp_get_archives( apply_filters( 'widget_archives_args', array(
+					'type'            => 'monthly',
+					'show_post_count' => $c,
+				) ) );
+				?>
+			</ul>
+		<?php
+		endif;
+		echo wp_kses_post( $args['after_widget'] );
+	}
+
+}
diff --git a/includes/widgets/class-amp-widget-categories.php b/includes/widgets/class-amp-widget-categories.php
new file mode 100644
index 00000000000..db4208357e6
--- /dev/null
+++ b/includes/widgets/class-amp-widget-categories.php
@@ -0,0 +1,91 @@
+<?php
+/**
+ * Class AMP_Widget_Categories
+ *
+ * @since 0.7.0
+ * @package AMP
+ */
+
+/**
+ * Class AMP_Widget_Categories
+ *
+ * @since 0.7.0
+ * @package AMP
+ */
+class AMP_Widget_Categories extends WP_Widget_Categories {
+
+	/**
+	 * Echoes the markup of the widget.
+	 *
+	 * Mainly copied from WP_Widget_Categories::widget()
+	 * There's now an id for the <form>.
+	 * And the dropdown is now filtered with 'wp_dropdown_cats.'
+	 * This enables adding an 'on' attribute, with the id of the form.
+	 * So changing the dropdown value will redirect to the category page, with valid AMP.
+	 *
+	 * @since 0.7.0
+	 *
+	 * @param array $args Widget display data.
+	 * @param array $instance Data for widget.
+	 * @return void
+	 */
+	public function widget( $args, $instance ) {
+		if ( ! is_amp_endpoint() ) {
+			parent::widget( $args, $instance );
+			return;
+		}
+
+		static $first_dropdown = true;
+		$title                 = ! empty( $instance['title'] ) ? $instance['title'] : __( 'Categories', 'default' );
+		/** This filter is documented in wp-includes/widgets/class-wp-widget-pages.php */
+		$title = apply_filters( 'widget_title', $title, $instance, $this->id_base );
+		$c     = ! empty( $instance['count'] ) ? '1' : '0';
+		$h     = ! empty( $instance['hierarchical'] ) ? '1' : '0';
+		$d     = ! empty( $instance['dropdown'] ) ? '1' : '0';
+		echo wp_kses_post( $args['before_widget'] );
+		if ( $title ) {
+			echo wp_kses_post( $args['before_title'] . $title . $args['after_title'] );
+		}
+		$cat_args = array(
+			'orderby'      => 'name',
+			'show_count'   => $c,
+			'hierarchical' => $h,
+		);
+		if ( $d ) :
+			$form_id = sprintf( 'widget-categories-dropdown-%d', $this->number );
+			printf( '<form action="%s" method="get" target="_top" id="%s">', esc_url( home_url() ), esc_attr( $form_id ) );
+			$dropdown_id    = ( $first_dropdown ) ? 'cat' : "{$this->id_base}-dropdown-{$this->number}";
+			$first_dropdown = false;
+			echo '<label class="screen-reader-text" for="' . esc_attr( $dropdown_id ) . '">' . esc_html( $title ) . '</label>';
+			$cat_args['show_option_none'] = __( 'Select Category', 'default' );
+			$cat_args['id']               = $dropdown_id;
+
+			$dropdown = wp_dropdown_categories( array_merge(
+				/** This filter is documented in wp-includes/widgets/class-wp-widget-categories.php */
+				apply_filters( 'widget_categories_dropdown_args', $cat_args, $instance ),
+				array( 'echo' => false )
+			) );
+			$dropdown = preg_replace(
+				'/(?<=<select\b)/',
+				sprintf( '<select on="change:%s.submit"', esc_attr( $form_id ) ),
+				$dropdown,
+				1
+			);
+			echo $dropdown; // WPCS: XSS OK.
+			echo '</form>';
+		else :
+			?>
+			<ul>
+			<?php
+			$cat_args['title_li'] = '';
+
+			/** This filter is documented in wp-includes/widgets/class-wp-widget-categories.php */
+			wp_list_categories( apply_filters( 'widget_categories_args', $cat_args, $instance ) );
+			?>
+			</ul>
+		<?php
+		endif;
+		echo wp_kses_post( $args['after_widget'] );
+	}
+
+}
diff --git a/includes/widgets/class-amp-widget-recent-comments.php b/includes/widgets/class-amp-widget-recent-comments.php
new file mode 100644
index 00000000000..6162344df05
--- /dev/null
+++ b/includes/widgets/class-amp-widget-recent-comments.php
@@ -0,0 +1,38 @@
+<?php
+/**
+ * Class AMP_Widget_Recent_Comments
+ *
+ * @since 0.7.0
+ * @package AMP
+ */
+
+/**
+ * Class AMP_Widget_Recent_Comments
+ *
+ * @since 0.7.0
+ * @package AMP
+ */
+class AMP_Widget_Recent_Comments extends WP_Widget_Recent_Comments {
+
+	/**
+	 * Instantiates the widget, and prevents inline styling.
+	 *
+	 * @since 0.7.0
+	 */
+	public function __construct() {
+		parent::__construct();
+		add_filter( 'wp_head', array( $this, 'remove_head_style_in_amp' ), 0 );
+	}
+
+	/**
+	 * Prevent recent comments widget style from printing in AMP,
+	 *
+	 * @since 0.7.0
+	 */
+	public function remove_head_style_in_amp() {
+		if ( is_amp_endpoint() ) {
+			add_filter( 'show_recent_comments_widget_style', '__return_false' );
+		}
+	}
+
+}
diff --git a/phpcs.xml b/phpcs.xml
index 30f5ea64606..a64861cc5c1 100644
--- a/phpcs.xml
+++ b/phpcs.xml
@@ -7,7 +7,7 @@
 
 	<rule ref="WordPress.WP.I18n">
 		<properties>
-			<property name="text_domain" value="amp" />
+			<property name="text_domain" value="amp,default" />
 		</properties>
 	</rule>
 
diff --git a/tests/test-class-amp-theme-support.php b/tests/test-class-amp-theme-support.php
index 0b15e7f1165..da03d44345b 100644
--- a/tests/test-class-amp-theme-support.php
+++ b/tests/test-class-amp-theme-support.php
@@ -68,6 +68,23 @@ public function test_is_paired_available() {
 		$this->assertFalse( AMP_Theme_Support::is_paired_available() );
 	}
 
+	/**
+	 * Test register_widgets().
+	 *
+	 * @covers AMP_Theme_Support::register_widgets()
+	 * @global WP_Widget_Factory $wp_widget_factory
+	 */
+	public function test_register_widgets() {
+		global $wp_widget_factory;
+		remove_all_actions( 'widgets_init' );
+		$wp_widget_factory->widgets = array();
+		wp_widgets_init();
+		AMP_Theme_Support::register_widgets();
+
+		$this->assertArrayNotHasKey( 'WP_Widget_Categories', $wp_widget_factory->widgets );
+		$this->assertArrayHasKey( 'AMP_Widget_Categories', $wp_widget_factory->widgets );
+	}
+
 	/**
 	 * Test finish_output_buffering.
 	 *
diff --git a/tests/test-class-amp-widget-archives.php b/tests/test-class-amp-widget-archives.php
new file mode 100644
index 00000000000..bef6d8639ee
--- /dev/null
+++ b/tests/test-class-amp-widget-archives.php
@@ -0,0 +1,73 @@
+<?php
+/**
+ * Tests for class AMP_Widget_Archives.
+ *
+ * @package AMP
+ */
+
+/**
+ * Tests for class AMP_Widget_Archives.
+ *
+ * @package AMP
+ */
+class Test_AMP_Widget_Archives extends WP_UnitTestCase {
+
+	/**
+	 * Instance of the widget.
+	 *
+	 * @var object.
+	 */
+	public $widget;
+
+	/**
+	 * Setup.
+	 *
+	 * @inheritdoc
+	 */
+	public function setUp() {
+		parent::setUp();
+		add_theme_support( 'amp' );
+		wp_maybe_load_widgets();
+		AMP_Theme_Support::init();
+		$this->widget = new AMP_Widget_Archives();
+	}
+
+	/**
+	 * Test construct().
+	 *
+	 * @see AMP_Widget_Archives::__construct().
+	 */
+	public function test_construct() {
+		$this->assertEquals( 'AMP_Widget_Archives', get_class( $this->widget ) );
+		$this->assertEquals( 'archives', $this->widget->id_base );
+		$this->assertEquals( 'Archives', $this->widget->name );
+		$this->assertEquals( 'widget_archive', $this->widget->widget_options['classname'] );
+		$this->assertEquals( true, $this->widget->widget_options['customize_selective_refresh'] );
+		$this->assertEquals( 'A monthly archive of your site&#8217;s Posts.', $this->widget->widget_options['description'] );
+	}
+
+	/**
+	 * Test widget().
+	 *
+	 * @see AMP_Widget_Archives::widget().
+	 */
+	public function test_widget() {
+		$arguments = array(
+			'before_widget' => '<div>',
+			'after_widget'  => '</div>',
+			'before_title'  => '<h2>',
+			'after_title'   => '</h2>',
+		);
+		$instance  = array(
+			'title'    => 'Test Archives Widget',
+			'dropdown' => 1,
+		);
+		ob_start();
+		$this->widget->widget( $arguments, $instance );
+		$output = ob_get_clean();
+
+		$this->assertContains( 'on="change:AMP.navigateTo(url=event.value)"', $output );
+		$this->assertNotContains( 'onchange=', $output );
+	}
+
+}
diff --git a/tests/test-class-amp-widget-categories.php b/tests/test-class-amp-widget-categories.php
new file mode 100644
index 00000000000..b79bc42dea2
--- /dev/null
+++ b/tests/test-class-amp-widget-categories.php
@@ -0,0 +1,73 @@
+<?php
+/**
+ * Tests for class AMP_Widget_Categories.
+ *
+ * @package AMP
+ */
+
+/**
+ * Tests for class AMP_Widget_Categories.
+ *
+ * @package AMP
+ */
+class Test_AMP_Widget_Categories extends WP_UnitTestCase {
+
+	/**
+	 * Instance of the widget.
+	 *
+	 * @var object.
+	 */
+	public $widget;
+
+	/**
+	 * Setup.
+	 *
+	 * @inheritdoc
+	 */
+	public function setUp() {
+		parent::setUp();
+		add_theme_support( 'amp ' );
+		wp_maybe_load_widgets();
+		AMP_Theme_Support::init();
+		$this->widget = new AMP_Widget_Categories();
+	}
+
+	/**
+	 * Test construct().
+	 *
+	 * @covers AMP_Widget_Categories::__construct()
+	 */
+	public function test_construct() {
+		$this->assertEquals( 'AMP_Widget_Categories', get_class( $this->widget ) );
+		$this->assertEquals( 'categories', $this->widget->id_base );
+		$this->assertEquals( 'Categories', $this->widget->name );
+		$this->assertEquals( 'widget_categories', $this->widget->widget_options['classname'] );
+		$this->assertEquals( true, $this->widget->widget_options['customize_selective_refresh'] );
+		$this->assertEquals( 'A list or dropdown of categories.', $this->widget->widget_options['description'] );
+	}
+
+	/**
+	 * Test widget().
+	 *
+	 * @covers AMP_Widget_Categories::widget()
+	 */
+	public function test_widget() {
+		$arguments = array(
+			'before_widget' => '<div>',
+			'after_widget'  => '</div>',
+			'before_title'  => '<h2>',
+			'after_title'   => '</h2>',
+		);
+		$instance  = array(
+			'title'    => 'Test Categories Widget',
+			'dropdown' => 1,
+		);
+		ob_start();
+		$this->widget->widget( $arguments, $instance );
+		$output = ob_get_clean();
+
+		$this->assertContains( 'on="change:', $output );
+		$this->assertNotContains( '<script type=', $output );
+	}
+
+}
diff --git a/tests/test-class-amp-widget-recent-comments.php b/tests/test-class-amp-widget-recent-comments.php
new file mode 100644
index 00000000000..4d74f160a8b
--- /dev/null
+++ b/tests/test-class-amp-widget-recent-comments.php
@@ -0,0 +1,69 @@
+<?php
+/**
+ * Tests for class AMP_Widget_Recent_Comments.
+ *
+ * @package AMP
+ */
+
+/**
+ * Tests for class AMP_Widget_Recent_Comments.
+ *
+ * @package AMP
+ */
+class Test_AMP_Widget_Recent_Comments extends WP_UnitTestCase {
+
+	/**
+	 * Setup.
+	 *
+	 * @inheritdoc
+	 */
+	public function setUp() {
+		parent::setUp();
+		add_theme_support( 'amp' );
+	}
+
+	/**
+	 * Test construct().
+	 *
+	 * @covers AMP_Widget_Recent_Comments::__construct()
+	 */
+	public function test_construct() {
+		add_theme_support( 'amp' );
+		$widget = new AMP_Widget_Recent_Comments();
+		$this->assertEquals( 'recent-comments', $widget->id_base );
+		$this->assertEquals( 'Recent Comments', $widget->name );
+		$this->assertEquals( 'widget_recent_comments', $widget->widget_options['classname'] );
+		$this->assertEquals( true, $widget->widget_options['customize_selective_refresh'] );
+		$this->assertEquals( 'Your site&#8217;s most recent comments.', $widget->widget_options['description'] );
+		$this->assertSame( 0, has_action( 'wp_head', array( $widget, 'remove_head_style_in_amp' ) ) );
+	}
+
+	/**
+	 * Test remove_head_style_in_amp.
+	 *
+	 * @covers AMP_Widget_Recent_Comments::remove_head_style_in_amp()
+	 */
+	public function test_remove_head_style_in_amp() {
+		new AMP_Widget_Recent_Comments();
+		$this->assertTrue( apply_filters( 'show_recent_comments_widget_style', true ) );
+		ob_start();
+		do_action( 'wp_head' );
+		ob_end_clean();
+		$this->assertFalse( apply_filters( 'show_recent_comments_widget_style', true ) );
+	}
+
+	/**
+	 * Test remove_head_style_in_amp when not in AMP.
+	 *
+	 * @covers AMP_Widget_Recent_Comments::remove_head_style_in_amp()
+	 */
+	public function test_remove_head_style_in_amp_not() {
+		remove_theme_support( 'amp' );
+		new AMP_Widget_Recent_Comments();
+		$this->assertTrue( apply_filters( 'show_recent_comments_widget_style', true ) );
+		ob_start();
+		do_action( 'wp_head' );
+		ob_end_clean();
+		$this->assertTrue( apply_filters( 'show_recent_comments_widget_style', true ) );
+	}
+}