diff --git a/docs/components/avatar.md b/docs/components/avatar.md
index 5191aa71..a48907b5 100644
--- a/docs/components/avatar.md
+++ b/docs/components/avatar.md
@@ -4,15 +4,17 @@
 
 Avatars are used to represent a person or object.
 
+Like [images](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/img), you should always provide `alt` text for avatars as alternate text for assistive devices.
+
 ```html preview
-<sl-avatar></sl-avatar>
+<sl-avatar alt="User avatar"></sl-avatar>
 ```
 
 ```jsx react
 import { SlAvatar } from '@shoelace-style/shoelace/dist/react';
 
 const App = () => (
-  <SlAvatar>Button</SlAvatar>
+  <SlAvatar alt="User avatar" />
 );
 ```
 
@@ -25,7 +27,7 @@ To use an image for the avatar, set the `image` and `alt` attributes. This will
 ```html preview
 <sl-avatar
   image="https://images.unsplash.com/photo-1529778873920-4da4926a72c2?ixlib=rb-1.2.1&auto=format&fit=crop&w=300&q=80"
-  alt="Gray tabby kitten looking down"
+  alt="Avatar of a gray tabby kitten looking down"
 ></sl-avatar>
 ```
 
@@ -35,7 +37,7 @@ import { SlAvatar } from '@shoelace-style/shoelace/dist/react';
 const App = () => (
   <SlAvatar
     image="https://images.unsplash.com/photo-1529778873920-4da4926a72c2?ixlib=rb-1.2.1&auto=format&fit=crop&w=300&q=80"
-    alt="Gray tabby kitten looking down"
+    alt="Avatar of a gray tabby kitten looking down"
   />
 );
 ```
@@ -45,14 +47,14 @@ const App = () => (
 When you don't have an image to use, you can set the `initials` attribute to show something more personalized than an icon.
 
 ```html preview
-<sl-avatar initials="SL"></sl-avatar>
+<sl-avatar initials="SL" alt="Avatar with initials: SL"></sl-avatar>
 ```
 
 ```jsx react
 import { SlAvatar } from '@shoelace-style/shoelace/dist/react';
 
 const App = () => (
-  <SlAvatar initials="SL" />
+  <SlAvatar initials="SL" alt="Avatar with initials: SL" />
 );
 ```
 
@@ -61,15 +63,15 @@ const App = () => (
 When no image or initials are set, an icon will be shown. The default avatar shows a generic "user" icon, but you can customize this with the `icon` slot.
 
 ```html preview
-<sl-avatar>
+<sl-avatar alt="Avatar with an image icon">
   <sl-icon slot="icon" name="image"></sl-icon>
 </sl-avatar>
 
-<sl-avatar>
+<sl-avatar alt="Avatar with an archive icon">
   <sl-icon slot="icon" name="archive"></sl-icon>
 </sl-avatar>
 
-<sl-avatar>
+<sl-avatar alt="Avatar with a briefcase icon">
   <sl-icon slot="icon" name="briefcase"></sl-icon>
 </sl-avatar>
 ```
@@ -79,15 +81,15 @@ import { SlAvatar, SlIcon } from '@shoelace-style/shoelace/dist/react';
 
 const App = () => (
   <>
-    <SlAvatar>
+    <SlAvatar alt="Avatar with an image icon">
       <SlIcon slot="icon" name="image" />
     </SlAvatar>
 
-    <SlAvatar>
+    <SlAvatar alt="Avatar with an archive icon">
       <SlIcon slot="icon" name="archive" />
     </SlAvatar>
 
-    <SlAvatar>
+    <SlAvatar alt="Avatar with a briefcase icon">
       <SlIcon slot="icon" name="briefcase" />
     </SlAvatar>
   </>
@@ -99,9 +101,9 @@ const App = () => (
 Avatars can be shaped using the `shape` attribute.
 
 ```html preview
-<sl-avatar shape="square"></sl-avatar>
-<sl-avatar shape="rounded"></sl-avatar>
-<sl-avatar shape="circle"></sl-avatar>
+<sl-avatar shape="square" alt="Square avatar"></sl-avatar>
+<sl-avatar shape="rounded" alt="Rounded avatar"></sl-avatar>
+<sl-avatar shape="circle" alt="Circle avatar"></sl-avatar>
 ```
 
 ```jsx react
@@ -109,9 +111,9 @@ import { SlAvatar, SlIcon } from '@shoelace-style/shoelace/dist/react';
 
 const App = () => (
   <>
-    <SlAvatar shape="square" />
-    <SlAvatar shape="rounded" />
-    <SlAvatar shape="circle" />
+    <SlAvatar shape="square" alt="Square avatar" />
+    <SlAvatar shape="rounded" alt="Rounded avatar" />
+    <SlAvatar shape="circle" alt="Circle avatar" />
   </>
 );
 ```
@@ -122,10 +124,25 @@ You can group avatars with a few lines of CSS.
 
 ```html preview
 <div class="avatar-group">
-  <sl-avatar image="https://images.unsplash.com/photo-1490150028299-bf57d78394e0?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&q=80&crop=right"></sl-avatar>
-  <sl-avatar image="https://images.unsplash.com/photo-1503454537195-1dcabb73ffb9?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&crop=left&q=80"></sl-avatar>
-  <sl-avatar image="https://images.unsplash.com/photo-1456439663599-95b042d50252?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&crop=left&q=80"></sl-avatar>
-  <sl-avatar image="https://images.unsplash.com/flagged/photo-1554078875-e37cb8b0e27d?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&crop=top&q=80"></sl-avatar>
+  <sl-avatar 
+    image="https://images.unsplash.com/photo-1490150028299-bf57d78394e0?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&q=80&crop=right"
+    alt="Avatar 1 of 4"
+  ></sl-avatar>
+
+  <sl-avatar 
+    image="https://images.unsplash.com/photo-1503454537195-1dcabb73ffb9?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&crop=left&q=80"
+    alt="Avatar 2 of 4"
+  ></sl-avatar>
+
+  <sl-avatar 
+    image="https://images.unsplash.com/photo-1456439663599-95b042d50252?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&crop=left&q=80"
+    alt="Avatar 3 of 4"
+  ></sl-avatar>
+
+  <sl-avatar 
+    image="https://images.unsplash.com/flagged/photo-1554078875-e37cb8b0e27d?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&crop=top&q=80"
+    alt="Avatar 4 of 4"
+  ></sl-avatar>
 </div>
 
 <style>
@@ -155,10 +172,25 @@ const css = `
 const App = () => (
   <>
     <div className="avatar-group">
-      <SlAvatar image="https://images.unsplash.com/photo-1490150028299-bf57d78394e0?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&q=80&crop=right" />
-      <SlAvatar image="https://images.unsplash.com/photo-1503454537195-1dcabb73ffb9?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&crop=left&q=80" />
-      <SlAvatar image="https://images.unsplash.com/photo-1456439663599-95b042d50252?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&crop=left&q=80" />
-      <SlAvatar image="https://images.unsplash.com/flagged/photo-1554078875-e37cb8b0e27d?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&crop=top&q=80" />
+      <SlAvatar 
+        image="https://images.unsplash.com/photo-1490150028299-bf57d78394e0?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&q=80&crop=right" 
+        alt="Avatar 1 of 4" 
+      />
+
+      <SlAvatar 
+        image="https://images.unsplash.com/photo-1503454537195-1dcabb73ffb9?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&crop=left&q=80" 
+        alt="Avatar 2 of 4" 
+      />
+      
+      <SlAvatar 
+        image="https://images.unsplash.com/photo-1456439663599-95b042d50252?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&crop=left&q=80" 
+        alt="Avatar 3 of 4" 
+      />
+      
+      <SlAvatar 
+        image="https://images.unsplash.com/flagged/photo-1554078875-e37cb8b0e27d?ixid=MXwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHw%3D&ixlib=rb-1.2.1&auto=format&fit=crop&w=256&h=256&crop=top&q=80" 
+        alt="Avatar 4 of 4" 
+      />
     </div>
 
     <style>{css}</style>    
diff --git a/docs/index.html b/docs/index.html
index 3a3f9180..31767c86 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -8,10 +8,7 @@
       name="description"
       content="Shoelace provides a collection of professionally designed, every day UI components built on a framework-agnostic technology."
     />
-    <meta
-      name="viewport"
-      content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0"
-    />
+    <meta name="viewport" content="width=device-width, initial-scale=1" />
     <meta name="custom-elements-manifest" content="dist/custom-elements.json" />
     <meta property="og:title" content="Shoelace" />
     <meta
diff --git a/docs/resources/changelog.md b/docs/resources/changelog.md
index 30d8a965..11e63493 100644
--- a/docs/resources/changelog.md
+++ b/docs/resources/changelog.md
@@ -8,6 +8,10 @@ _During the beta period, these restrictions may be relaxed in the event of a mis
 
 ## Next
 
+- Improved a11y of `<sl-avatar>` by representing it as an image with an `alt` [#579](https://github.com/shoelace-style/shoelace/issues/579)
+- Improved a11y of the scroll buttons in `<sl-tab-group>`
+- Improved a11y of the close button in `<sl-tab>`
+- Improved a11y of `<sl-tab-panel>` by removing an invalid `aria-selected` attribute [#579](https://github.com/shoelace-style/shoelace/issues/579)
 - Moved `role` from the shadow root to the host element in `<sl-menu>`
 - Removed redundant `role="menu"` in `<sl-dropdown>`
 - Slightly faster animations for showing and hiding `<sl-dropdown>`
diff --git a/src/components/avatar/avatar.test.ts b/src/components/avatar/avatar.test.ts
index e27aae69..165b8d74 100644
--- a/src/components/avatar/avatar.test.ts
+++ b/src/components/avatar/avatar.test.ts
@@ -8,7 +8,7 @@ describe('<sl-avatar>', () => {
 
   describe('when provided no parameters', async () => {
     before(async () => {
-      el = await fixture<SlAvatar>(html` <sl-avatar></sl-avatar> `);
+      el = await fixture<SlAvatar>(html` <sl-avatar alt="Avatar"></sl-avatar> `);
     });
 
     it('passes accessibility test', async () => {
@@ -71,7 +71,7 @@ describe('<sl-avatar>', () => {
   describe('when provided initials parameter', async () => {
     const initials = 'SL';
     before(async () => {
-      el = await fixture<SlAvatar>(html`<sl-avatar initials="${initials}"></sl-avatar>`);
+      el = await fixture<SlAvatar>(html`<sl-avatar initials="${initials}" alt="Avatar"></sl-avatar>`);
     });
 
     it('passes accessibility test', async () => {
@@ -88,7 +88,7 @@ describe('<sl-avatar>', () => {
   ['square', 'rounded', 'circle'].forEach(shape => {
     describe(`when passed a shape attribute ${shape}`, () => {
       before(async () => {
-        el = await fixture<SlAvatar>(html`<sl-avatar shape="${shape}"></sl-avatar>`);
+        el = await fixture<SlAvatar>(html`<sl-avatar shape="${shape as any}" alt="Shaped avatar"></sl-avatar>`);
       });
 
       it('passes accessibility test', async () => {
@@ -106,7 +106,7 @@ describe('<sl-avatar>', () => {
 
   describe('when passed a <span>, on slot "icon"', async () => {
     before(async () => {
-      el = await fixture<SlAvatar>(html`<sl-avatar><span slot="icon">random content</span></sl-avatar>`);
+      el = await fixture<SlAvatar>(html`<sl-avatar alt="Avatar"><span slot="icon">random content</span></sl-avatar>`);
     });
 
     it('passes accessibility test', async () => {
diff --git a/src/components/avatar/avatar.ts b/src/components/avatar/avatar.ts
index 14bad898..df8c2046 100644
--- a/src/components/avatar/avatar.ts
+++ b/src/components/avatar/avatar.ts
@@ -48,12 +48,13 @@ export default class SlAvatar extends LitElement {
           'avatar--rounded': this.shape === 'rounded',
           'avatar--square': this.shape === 'square'
         })}
+        role="img"
         aria-label=${this.alt}
       >
         ${this.initials
           ? html` <div part="initials" class="avatar__initials">${this.initials}</div> `
           : html`
-              <div part="icon" class="avatar__icon">
+              <div part="icon" class="avatar__icon" aria-hidden="true">
                 <slot name="icon">
                   <sl-icon name="person-fill" library="system"></sl-icon>
                 </slot>
diff --git a/src/components/tab-group/tab-group.ts b/src/components/tab-group/tab-group.ts
index a468c8f3..ef13a2b5 100644
--- a/src/components/tab-group/tab-group.ts
+++ b/src/components/tab-group/tab-group.ts
@@ -339,6 +339,7 @@ export default class SlTabGroup extends LitElement {
     this.syncIndicator();
   }
 
+  // TODO - i18n scroll to start/end labels
   render() {
     return html`
       <div
@@ -362,6 +363,7 @@ export default class SlTabGroup extends LitElement {
                   exportparts="base:scroll-button"
                   name="chevron-left"
                   library="system"
+                  label="Scroll to start"
                   @click=${this.handleScrollToStart}
                 ></sl-icon-button>
               `
@@ -381,6 +383,7 @@ export default class SlTabGroup extends LitElement {
                   exportparts="base:scroll-button"
                   name="chevron-right"
                   library="system"
+                  label="Scroll to end"
                   @click=${this.handleScrollToEnd}
                 ></sl-icon-button>
               `
diff --git a/src/components/tab-panel/tab-panel.ts b/src/components/tab-panel/tab-panel.ts
index 700dfb80..5329d6a8 100644
--- a/src/components/tab-panel/tab-panel.ts
+++ b/src/components/tab-panel/tab-panel.ts
@@ -35,13 +35,7 @@ export default class SlTabPanel extends LitElement {
     this.style.display = this.active ? 'block' : 'none';
 
     return html`
-      <div
-        part="base"
-        class="tab-panel"
-        role="tabpanel"
-        aria-selected=${this.active ? 'true' : 'false'}
-        aria-hidden=${this.active ? 'false' : 'true'}
-      >
+      <div part="base" class="tab-panel" role="tabpanel" aria-hidden=${this.active ? 'false' : 'true'}>
         <slot></slot>
       </div>
     `;
diff --git a/src/components/tab/tab.ts b/src/components/tab/tab.ts
index e22f6f87..5c41821f 100644
--- a/src/components/tab/tab.ts
+++ b/src/components/tab/tab.ts
@@ -59,6 +59,7 @@ export default class SlTab extends LitElement {
     // If the user didn't provide an ID, we'll set one so we can link tabs and tab panels with aria labels
     this.id = this.id || this.componentId;
 
+    // TODO - i18n close label
     return html`
       <div
         part="base"
@@ -79,11 +80,11 @@ export default class SlTab extends LitElement {
               <sl-icon-button
                 name="x"
                 library="system"
+                label="Close"
                 exportparts="base:close-button"
                 class="tab__close-button"
                 @click=${this.handleCloseClick}
                 tabindex="-1"
-                aria-hidden="true"
               ></sl-icon-button>
             `
           : ''}