diff --git src/wp-admin/includes/ajax-actions.php src/wp-admin/includes/ajax-actions.php
index db22db2..ccc880b 100644
--- src/wp-admin/includes/ajax-actions.php
+++ src/wp-admin/includes/ajax-actions.php
@@ -3213,6 +3213,8 @@ function wp_ajax_query_themes() {
 		wp_send_json_error();
 	}
 
+	$current_theme = get_stylesheet();
+
 	$update_php = network_admin_url( 'update.php?action=install-theme' );
 	foreach ( $api->themes as &$theme ) {
 		$theme->install_url = add_query_arg(
@@ -3268,6 +3270,7 @@ function wp_ajax_query_themes() {
 		);
 		$theme->num_ratings = number_format_i18n( $theme->num_ratings );
 		$theme->preview_url = set_url_scheme( $theme->preview_url );
+		$theme->active      = ( $theme->slug === $current_theme );
 	}
 
 	wp_send_json_success( $api );
diff --git src/wp-admin/theme-install.php src/wp-admin/theme-install.php
index 369cb87..7489272 100644
--- src/wp-admin/theme-install.php
+++ src/wp-admin/theme-install.php
@@ -275,21 +275,32 @@ if ( $tab ) {
 	</div>
 
 	<div class="theme-id-container">
-		<h3 class="theme-name">{{ data.name }}</h3>
-
-		<div class="theme-actions">
-			<# if ( data.installed ) { #>
+		<# if ( data.active ) { #>
+			<h3 class="theme-name">
 				<?php
 				/* translators: %s: Theme name */
-				$aria_label = sprintf( _x( 'Activate %s', 'theme' ), '{{ data.name }}' );
+				printf( __( '<span>Active:</span> %s' ), '{{{ data.name }}}' );
 				?>
-				<# if ( data.activate_url ) { #>
-					<a class="button button-primary activate" href="{{ data.activate_url }}" aria-label="<?php echo esc_attr( $aria_label ); ?>"><?php _e( 'Activate' ); ?></a>
-				<# } #>
-				<# if ( data.customize_url ) { #>
-					<a class="button load-customize" href="{{ data.customize_url }}"><?php _e( 'Live Preview' ); ?></a>
+			</h3>
+		<# } else { #>
+			<h3 class="theme-name">{{ data.name }}</h3>
+		<# } #>
+
+		<div class="theme-actions">
+			<# if ( data.installed ) { #>
+				<# if ( ! data.active ) { #>
+					<# if ( data.activate_url ) { #>
+						<a class="button button-primary activate" href="{{ data.activate_url }}" aria-label="<?php echo esc_attr( $aria_label ); ?>"><?php _e( 'Activate' ); ?></a>
+					<# } #>
+					<# if ( data.customize_url ) { #>
+						<a class="button load-customize" href="{{ data.customize_url }}"><?php _e( 'Live Preview' ); ?></a>
+					<# } else { #>
+						<button class="button preview install-theme-preview"><?php _e( 'Preview' ); ?></button>
+					<# } #>
 				<# } else { #>
-					<button class="button preview install-theme-preview"><?php _e( 'Preview' ); ?></button>
+					<# if ( data.customize_url ) { #>
+						<a class="button button-primary customize load-customize hide-if-no-customize" href="{{{ data.customize_url }}}"><?php _e( 'Customize' ); ?></a>
+					<# } #>
 				<# } #>
 			<# } else { #>
 				<?php
@@ -314,14 +325,25 @@ if ( $tab ) {
 			<button class="previous-theme"><span class="screen-reader-text"><?php _e( 'Previous theme' ); ?></span></button>
 			<button class="next-theme"><span class="screen-reader-text"><?php _e( 'Next theme' ); ?></span></button>
 			<# if ( data.installed ) { #>
-				<a class="button button-primary activate" href="{{ data.activate_url }}"><?php _e( 'Activate' ); ?></a>
+				<# if ( ! data.active ) { #> 
+					<a class="button button-primary activate" href="{{ data.activate_url }}"><?php _e( 'Activate' ); ?></a>
+				<# } #>
 			<# } else { #>
 				<a href="{{ data.install_url }}" class="button button-primary theme-install" data-name="{{ data.name }}" data-slug="{{ data.id }}"><?php _e( 'Install' ); ?></a>
 			<# } #>
 		</div>
 		<div class="wp-full-overlay-sidebar-content">
 			<div class="install-theme-info">
-				<h3 class="theme-name">{{ data.name }}</h3>
+				<# if ( data.active ) { #>
+					<h3 class="theme-name">
+						<?php
+						/* translators: %s: Theme name */
+						printf( __( '<span>Active:</span> %s' ), '{{{ data.name }}}' );
+						?>
+					</h3>
+				<# } else { #>
+					<h3 class="theme-name">{{ data.name }}</h3>
+				<# } #>
 					<span class="theme-by">
 						<?php
 						/* translators: %s: Theme author name */