diff --git a/blocks/api/categories.js b/blocks/api/categories.js
index e1343f3b984632..0e97bfdf8eae90 100644
--- a/blocks/api/categories.js
+++ b/blocks/api/categories.js
@@ -5,7 +5,7 @@
  * @var {Array} categories
  */
 const categories = [
-	{ slug: 'common', title: 'Common' }
+	{ slug: 'common', title: 'Common blocks' }
 ];
 
 /**
diff --git a/editor/components/icon-button/style.scss b/editor/components/icon-button/style.scss
index e3e6d84083ea09..bf2c4915d672eb 100644
--- a/editor/components/icon-button/style.scss
+++ b/editor/components/icon-button/style.scss
@@ -1,8 +1,7 @@
 .editor-icon-button {
 	display: flex;
 	align-items: center;
-	min-width: 36px;
-	height: 36px;
+	padding: 8px;
 	border: none;
 	background: none;
 	color: $dark-gray-500;
diff --git a/editor/components/inserter/index.js b/editor/components/inserter/index.js
index ad9eee3450c057..cb74a423946b6a 100644
--- a/editor/components/inserter/index.js
+++ b/editor/components/inserter/index.js
@@ -49,7 +49,9 @@ class Inserter extends wp.element.Component {
 					icon="insert"
 					label={ wp.i18n.__( 'Insert block' ) }
 					onClick={ this.toggle }
-					className="editor-inserter__toggle" />
+					className="editor-inserter__toggle"
+					aria-haspopup="true"
+					aria-expanded={ opened ? 'true' : 'false' } />
 				{ opened && <InserterMenu position={ position } onSelect={ this.close } /> }
 			</div>
 		);
diff --git a/editor/components/inserter/menu.js b/editor/components/inserter/menu.js
index 1e4a08b1ac85ab..f6a5954faf2308 100644
--- a/editor/components/inserter/menu.js
+++ b/editor/components/inserter/menu.js
@@ -16,6 +16,7 @@ class InserterMenu extends wp.element.Component {
 			filterValue: ''
 		};
 		this.filter = this.filter.bind( this );
+		this.instanceId = this.constructor.instances++;
 	}
 
 	filter( event ) {
@@ -55,10 +56,22 @@ class InserterMenu extends wp.element.Component {
 					{ categories
 						.map( ( category ) => !! blocksByCategory[ category.slug ] && (
 							<div key={ category.slug }>
-								<div className="editor-inserter__separator">{ category.title }</div>
-								<div className="editor-inserter__category-blocks">
+								<div
+									className="editor-inserter__separator"
+									id={ `editor-inserter__separator-${ category.slug }-${ this.instanceId }` }
+									aria-hidden="true"
+								>
+									{ category.title }
+								</div>
+								<div
+									className="editor-inserter__category-blocks"
+									role="menu"
+									tabIndex="0"
+									aria-labelledby={ `editor-inserter__separator-${ category.slug }-${ this.instanceId }` }
+								>
 									{ blocksByCategory[ category.slug ].map( ( { slug, title, icon } ) => (
 										<button
+											role="menuitem"
 											key={ slug }
 											className="editor-inserter__block"
 											onClick={ this.selectBlock( slug ) }
@@ -72,7 +85,11 @@ class InserterMenu extends wp.element.Component {
 						) )
 					}
 				</div>
+				<label htmlFor={ `editor-inserter__search-${ this.instanceId }` } className="screen-reader-text">
+					{ wp.i18n.__( 'Search blocks' ) }
+				</label>
 				<input
+					id={ `editor-inserter__search-${ this.instanceId }` }
 					type="search"
 					placeholder={ wp.i18n.__( 'Search…' ) }
 					className="editor-inserter__search"
@@ -83,6 +100,8 @@ class InserterMenu extends wp.element.Component {
 	}
 }
 
+InserterMenu.instances = 0;
+
 export default connect(
 	undefined,
 	( dispatch ) => ( {
diff --git a/editor/components/inserter/style.scss b/editor/components/inserter/style.scss
index 6b4665f7f0afa7..183812df025db2 100644
--- a/editor/components/inserter/style.scss
+++ b/editor/components/inserter/style.scss
@@ -18,10 +18,7 @@
 	background: none;
 	cursor: pointer;
 	border: none;
-	width: 36px;
-	height: 36px;
 	outline: none;
-	padding: 0;
 	transition: color .2s ease;
 
 	&:hover {
@@ -102,7 +99,7 @@
 }
 
 .editor-inserter__content {
-	max-height: 180px;
+	max-height: 186px;
 	overflow: auto;
 
 	&:focus {
@@ -136,15 +133,18 @@ input[type=search].editor-inserter__search {
 	width: 50%;
 	font-size: 12px;
 	color: $dark-gray-500;
+	margin: 0;
 	padding: 8px;
 	align-items: center;
 	cursor: pointer;
 	border: 1px solid transparent;
 	background: none;
+	line-height: 20px;
 
-	&:hover {
+	&:hover,
+	&:focus {
 		border: 1px solid $dark-gray-500;
-		position: relative;
+		outline: none;
 	}
 
 	&:active,
@@ -161,6 +161,7 @@ input[type=search].editor-inserter__search {
 
 .editor-inserter__separator {
 	display: block;
+	margin: 0;
 	padding: 4px 8px;
 	font-size: 11px;
 	font-weight: 600;
diff --git a/editor/components/toolbar/style.scss b/editor/components/toolbar/style.scss
index 806a43c26ae8a0..247b2ac58ed954 100644
--- a/editor/components/toolbar/style.scss
+++ b/editor/components/toolbar/style.scss
@@ -7,9 +7,9 @@
 
 .editor-toolbar__control.editor-button {
 	display: inline-flex;
+	align-items: flex-end;
 	margin: 3px;
 	margin-left: 0;
-	padding: 6px;
 	background: none;
 	border: 1px solid transparent;
 	outline: none;
@@ -39,9 +39,9 @@
 		font-family: $default-font;
 		font-size: 10px;
 		font-weight: bold;
-		position: absolute;
-		bottom: 8px;
-		right: 5px;
+		position: relative;
+		top: -1px;
+		margin-left: -3px;
 	}
 }