diff --git a/app/page.tsx b/app/page.tsx
index 4908edd..d033a6d 100644
--- a/app/page.tsx
+++ b/app/page.tsx
@@ -131,7 +131,7 @@ export default function Home() {
   return (
     <div className="min-h-screen bg-gradient-to-br from-slate-100 to-slate-200">
       {/* Header */}
-      <header className="bg-white shadow-md">
+      <header className="bg-white shadow-md" role="banner">
         <div className="max-w-7xl mx-auto px-4 py-4 flex items-center justify-between">
           <div className="flex items-center gap-4">
             <h1 className="text-2xl font-bold bg-gradient-to-r from-blue-600 to-purple-600 bg-clip-text text-transparent">
@@ -148,12 +148,15 @@ export default function Home() {
             <button
               onClick={() => setShowRules(!showRules)}
               className="text-gray-600 hover:text-gray-900 text-sm font-medium"
+              aria-label="Toggle game rules"
+              aria-expanded={showRules}
             >
               Rules
             </button>
             <button
               onClick={leaveRoom}
               className="bg-red-500 text-white px-4 py-2 rounded-lg text-sm font-semibold hover:bg-red-600 transition-colors"
+              aria-label="Leave current game"
             >
               Leave Game
             </button>
@@ -169,6 +172,9 @@ export default function Home() {
             animate={{ y: 0, opacity: 1 }}
             exit={{ y: -100, opacity: 0 }}
             className="fixed top-20 left-1/2 transform -translate-x-1/2 bg-red-500 text-white px-6 py-3 rounded-lg shadow-lg z-50"
+            role="alert"
+            aria-live="assertive"
+            aria-atomic="true"
           >
             {error}
           </motion.div>
@@ -184,6 +190,9 @@ export default function Home() {
             exit={{ opacity: 0 }}
             className="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center p-4 z-50"
             onClick={() => setShowRules(false)}
+            role="dialog"
+            aria-modal="true"
+            aria-labelledby="rules-title"
           >
             <motion.div
               initial={{ scale: 0.9 }}
@@ -192,7 +201,7 @@ export default function Home() {
               className="bg-white rounded-lg p-6 max-w-md"
               onClick={(e) => e.stopPropagation()}
             >
-              <h3 className="text-xl font-bold mb-4">How to Play</h3>
+              <h3 id="rules-title" className="text-xl font-bold mb-4">How to Play</h3>
               <ul className="space-y-2 text-sm text-gray-700">
                 <li>• Click on a tile to select it</li>
                 <li>• Click &quot;Place Left&quot; or &quot;Place Right&quot; to place it</li>
@@ -204,6 +213,7 @@ export default function Home() {
               <button
                 onClick={() => setShowRules(false)}
                 className="mt-4 w-full bg-blue-500 text-white py-2 rounded-lg"
+                aria-label="Close rules dialog"
               >
                 Close
               </button>
@@ -213,12 +223,12 @@ export default function Home() {
       </AnimatePresence>
 
       {/* Main game area */}
-      <div className="max-w-7xl mx-auto px-4 py-6">
+      <main className="max-w-7xl mx-auto px-4 py-6" role="main">
         <div className="grid lg:grid-cols-[1fr_300px] gap-6">
           {/* Left side - Game board and controls */}
           <div className="space-y-4">
             {/* Game info */}
-            <div className="bg-white rounded-lg shadow-md p-4">
+            <div className="bg-white rounded-lg shadow-md p-4" role="status" aria-live="polite" aria-atomic="true">
               <div className="flex items-center justify-between">
                 <div>
                   <div className="text-sm text-gray-600">Current Turn</div>
@@ -255,11 +265,12 @@ export default function Home() {
                     )}
                   </div>
                 )}
-                <div className="flex items-center gap-3 flex-wrap">
+                <div className="flex items-center gap-3 flex-wrap" role="group" aria-label="Game controls">
                   <button
                     onClick={() => handlePlaceTile('left')}
                     disabled={!selectedTile}
                     className="flex-1 bg-gradient-to-r from-blue-500 to-blue-600 text-white py-3 rounded-lg font-semibold disabled:opacity-50 disabled:cursor-not-allowed hover:shadow-lg transition-shadow"
+                    aria-label={selectedTile ? `Place tile ${selectedTile.left}-${selectedTile.right} on the left side` : 'Place tile on left side (select a tile first)'}
                   >
                     Place Left
                   </button>
@@ -267,6 +278,7 @@ export default function Home() {
                     onClick={() => handlePlaceTile('right')}
                     disabled={!selectedTile}
                     className="flex-1 bg-gradient-to-r from-purple-500 to-purple-600 text-white py-3 rounded-lg font-semibold disabled:opacity-50 disabled:cursor-not-allowed hover:shadow-lg transition-shadow"
+                    aria-label={selectedTile ? `Place tile ${selectedTile.left}-${selectedTile.right} on the right side` : 'Place tile on right side (select a tile first)'}
                   >
                     Place Right
                   </button>
@@ -274,6 +286,7 @@ export default function Home() {
                     <button
                       onClick={drawTile}
                       className="flex-1 bg-gradient-to-r from-green-500 to-green-600 text-white py-3 rounded-lg font-semibold hover:shadow-lg transition-shadow"
+                      aria-label={`Draw a tile from the boneyard (${gameState.boneyard.length} tiles remaining)`}
                     >
                       Draw Tile
                     </button>
@@ -282,6 +295,7 @@ export default function Home() {
                     <button
                       onClick={handlePass}
                       className="flex-1 bg-gradient-to-r from-yellow-500 to-yellow-600 text-white py-3 rounded-lg font-semibold hover:shadow-lg transition-shadow"
+                      aria-label="Pass your turn (no valid moves available)"
                     >
                       Pass Turn
                     </button>
@@ -303,7 +317,7 @@ export default function Home() {
           </div>
 
           {/* Right side - Other players */}
-          <div className="space-y-4">
+          <aside className="space-y-4" role="complementary" aria-label="Other players">
             <h3 className="text-lg font-semibold text-gray-700">Players</h3>
             {gameState.players
               .filter(p => p.id !== currentPlayerId)
@@ -338,10 +352,10 @@ export default function Home() {
                     ))}
                   </div>
                 </div>
-              ))}
-          </div>
+              )}
+          </aside>
         </div>
-      </div>
+      </main>
 
       {/* Game over modal */}
       {gameState.isGameOver && (
diff --git a/components/GameBoard.tsx b/components/GameBoard.tsx
index 0de9f07..408846d 100644
--- a/components/GameBoard.tsx
+++ b/components/GameBoard.tsx
@@ -163,7 +163,7 @@ export function GameBoard({ placedTiles, width = 1200, height = 700, className =
   };
 
   return (
-    <div className={className}>
+    <div className={className} role="region" aria-label="Game board">
       <canvas
         ref={canvasRef}
         width={width}
@@ -173,6 +173,8 @@ export function GameBoard({ placedTiles, width = 1200, height = 700, className =
         onMouseMove={handleMouseMove}
         onMouseUp={handleMouseUp}
         onMouseLeave={handleMouseUp}
+        role="img"
+        aria-label={`Domino board with ${placedTiles.length} tiles placed`}
       />
       {placedTiles.length > 0 && (
         <div className="mt-2 text-center text-sm text-gray-600">
diff --git a/components/GameOver.tsx b/components/GameOver.tsx
index 9cf29e7..64bf675 100644
--- a/components/GameOver.tsx
+++ b/components/GameOver.tsx
@@ -17,6 +17,9 @@ export function GameOver({ winner, players, onPlayAgain, onLeave }: GameOverProp
       initial={{ opacity: 0 }}
       animate={{ opacity: 1 }}
       className="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center p-4 z-50"
+      role="dialog"
+      aria-modal="true"
+      aria-labelledby="game-over-title"
     >
       <motion.div
         initial={{ scale: 0.8, y: 50 }}
@@ -32,7 +35,7 @@ export function GameOver({ winner, players, onPlayAgain, onLeave }: GameOverProp
           >
             {winner ? '🏆' : '🤝'}
           </motion.div>
-          <h2 className="text-3xl font-bold text-gray-800 mb-2">
+          <h2 id="game-over-title" className="text-3xl font-bold text-gray-800 mb-2">
             {winner ? 'Game Over!' : 'Game Blocked!'}
           </h2>
           {winner && (
@@ -91,6 +94,7 @@ export function GameOver({ winner, players, onPlayAgain, onLeave }: GameOverProp
             whileTap={{ scale: 0.98 }}
             onClick={onPlayAgain}
             className="w-full bg-gradient-to-r from-green-500 to-green-600 text-white py-3 rounded-lg font-semibold shadow-lg hover:shadow-xl transition-shadow"
+            aria-label="Start a new game"
           >
             Play Again
           </motion.button>
@@ -100,8 +104,9 @@ export function GameOver({ winner, players, onPlayAgain, onLeave }: GameOverProp
             whileTap={{ scale: 0.98 }}
             onClick={onLeave}
             className="w-full bg-gray-300 text-gray-700 py-3 rounded-lg font-semibold hover:bg-gray-400 transition-colors"
+            aria-label="Leave game and return to main menu"
           >
-            Back to Menu
+            Leave Game
           </motion.button>
         </div>
       </motion.div>
diff --git a/components/Lobby.tsx b/components/Lobby.tsx
index 6b04a15..43835c3 100644
--- a/components/Lobby.tsx
+++ b/components/Lobby.tsx
@@ -32,7 +32,7 @@ export function Lobby({ onCreateRoom, onJoinRoom, onStartAI, roomId }: LobbyProp
 
   if (mode === 'menu') {
     return (
-      <div className="min-h-screen bg-gradient-to-br from-blue-500 via-purple-500 to-pink-500 flex items-center justify-center p-4">
+      <main className="min-h-screen bg-gradient-to-br from-blue-500 via-purple-500 to-pink-500 flex items-center justify-center p-4" role="main">
         <motion.div
           initial={{ scale: 0.9, opacity: 0 }}
           animate={{ scale: 1, opacity: 1 }}
@@ -48,23 +48,28 @@ export function Lobby({ onCreateRoom, onJoinRoom, onStartAI, roomId }: LobbyProp
           <p className="text-center text-gray-600 mb-8">Online Multiplayer Game</p>
 
           <div className="space-y-4 mb-6">
+            <label htmlFor="player-name" className="sr-only">Your name</label>
             <input
+              id="player-name"
               type="text"
               placeholder="Enter your name"
               value={playerName}
               onChange={(e) => setPlayerName(e.target.value)}
               className="w-full px-4 py-3 border-2 border-gray-300 rounded-lg focus:border-blue-500 focus:outline-none transition-colors"
               maxLength={20}
+              aria-label="Enter your player name"
+              aria-required="true"
             />
           </div>
 
-          <div className="space-y-3">
+          <div className="space-y-3" role="group" aria-label="Game mode selection">
             <motion.button
               whileHover={{ scale: 1.02 }}
               whileTap={{ scale: 0.98 }}
               onClick={handleCreate}
               disabled={!playerName.trim()}
               className="w-full bg-gradient-to-r from-blue-500 to-blue-600 text-white py-3 rounded-lg font-semibold shadow-lg hover:shadow-xl transition-shadow disabled:opacity-50 disabled:cursor-not-allowed"
+              aria-label="Create a new multiplayer room"
             >
               Create Room
             </motion.button>
@@ -75,6 +80,7 @@ export function Lobby({ onCreateRoom, onJoinRoom, onStartAI, roomId }: LobbyProp
               onClick={() => setMode('join')}
               disabled={!playerName.trim()}
               className="w-full bg-gradient-to-r from-purple-500 to-purple-600 text-white py-3 rounded-lg font-semibold shadow-lg hover:shadow-xl transition-shadow disabled:opacity-50 disabled:cursor-not-allowed"
+              aria-label="Join an existing multiplayer room"
             >
               Join Room
             </motion.button>
@@ -85,6 +91,7 @@ export function Lobby({ onCreateRoom, onJoinRoom, onStartAI, roomId }: LobbyProp
               onClick={handleAI}
               disabled={!playerName.trim()}
               className="w-full bg-gradient-to-r from-green-500 to-green-600 text-white py-3 rounded-lg font-semibold shadow-lg hover:shadow-xl transition-shadow disabled:opacity-50 disabled:cursor-not-allowed"
+              aria-label="Start a game against computer AI"
             >
               Play vs AI
             </motion.button>
@@ -94,13 +101,13 @@ export function Lobby({ onCreateRoom, onJoinRoom, onStartAI, roomId }: LobbyProp
             <p>Built with Next.js, Canvas & Socket.IO</p>
           </div>
         </motion.div>
-      </div>
+      </main>
     );
   }
 
   if (mode === 'join') {
     return (
-      <div className="min-h-screen bg-gradient-to-br from-blue-500 via-purple-500 to-pink-500 flex items-center justify-center p-4">
+      <main className="min-h-screen bg-gradient-to-br from-blue-500 via-purple-500 to-pink-500 flex items-center justify-center p-4" role="main">
         <motion.div
           initial={{ scale: 0.9, opacity: 0 }}
           animate={{ scale: 1, opacity: 1 }}
@@ -109,13 +116,17 @@ export function Lobby({ onCreateRoom, onJoinRoom, onStartAI, roomId }: LobbyProp
           <h2 className="text-3xl font-bold text-center mb-6 text-gray-800">Join Room</h2>
 
           <div className="space-y-4 mb-6">
+            <label htmlFor="room-id" className="sr-only">Room ID</label>
             <input
+              id="room-id"
               type="text"
               placeholder="Enter Room ID"
               value={joinRoomId}
               onChange={(e) => setJoinRoomId(e.target.value.toUpperCase())}
               className="w-full px-4 py-3 border-2 border-gray-300 rounded-lg focus:border-purple-500 focus:outline-none transition-colors uppercase"
               maxLength={6}
+              aria-label="Enter the 6-character room ID"
+              aria-required="true"
             />
           </div>
 
@@ -126,6 +137,7 @@ export function Lobby({ onCreateRoom, onJoinRoom, onStartAI, roomId }: LobbyProp
               onClick={handleJoin}
               disabled={!joinRoomId.trim()}
               className="w-full bg-gradient-to-r from-purple-500 to-purple-600 text-white py-3 rounded-lg font-semibold shadow-lg hover:shadow-xl transition-shadow disabled:opacity-50 disabled:cursor-not-allowed"
+              aria-label="Join the room with entered ID"
             >
               Join Game
             </motion.button>
@@ -135,12 +147,13 @@ export function Lobby({ onCreateRoom, onJoinRoom, onStartAI, roomId }: LobbyProp
               whileTap={{ scale: 0.98 }}
               onClick={() => setMode('menu')}
               className="w-full bg-gray-300 text-gray-700 py-3 rounded-lg font-semibold hover:bg-gray-400 transition-colors"
+              aria-label="Go back to main menu"
             >
               Back
             </motion.button>
           </div>
         </motion.div>
-      </div>
+      </main>
     );
   }
 
diff --git a/components/PlayerHand.tsx b/components/PlayerHand.tsx
index ebf0bee..1f07c2e 100644
--- a/components/PlayerHand.tsx
+++ b/components/PlayerHand.tsx
@@ -20,7 +20,7 @@ export function PlayerHand({
   validTileIds,
 }: PlayerHandProps) {
   return (
-    <div className="bg-white rounded-lg shadow-lg p-4">
+    <div className="bg-white rounded-lg shadow-lg p-4" role="region" aria-label="Your tiles">
       <div className="flex items-center justify-between mb-3">
         <div className="flex items-center gap-3">
           <div className={`w-10 h-10 rounded-full flex items-center justify-center font-bold text-white ${
@@ -63,6 +63,16 @@ export function PlayerHand({
                   className={`relative ${
                     isPlayable && isCurrentPlayer ? 'cursor-pointer' : 'cursor-not-allowed'
                   }`}
+                  role="button"
+                  tabIndex={isPlayable && isCurrentPlayer ? 0 : -1}
+                  aria-label={`Tile ${tile.left}-${tile.right}${isSelected ? ' (selected)' : ''}${!isPlayable ? ' (cannot be played)' : ''}`}
+                  aria-pressed={isSelected}
+                  onKeyDown={(e) => {
+                    if ((e.key === 'Enter' || e.key === ' ') && isPlayable && isCurrentPlayer) {
+                      e.preventDefault();
+                      onTileClick(tile.id);
+                    }
+                  }}
                 >
                   <DominoTileSVG
                     tile={tile}
@@ -96,6 +106,8 @@ function DominoTileSVG({ tile, isSelected, isPlayable }: DominoTileSVGProps) {
       className={`transition-all ${
         isSelected ? 'ring-4 ring-blue-500 rounded' : ''
       } ${!isPlayable ? 'opacity-50' : ''}`}
+      role="img"
+      aria-label={`Domino tile: ${tile.left} and ${tile.right}`}
     >
       {/* Background */}
       <rect
diff --git a/components/WaitingRoom.tsx b/components/WaitingRoom.tsx
index 0916fbd..f0fa565 100644
--- a/components/WaitingRoom.tsx
+++ b/components/WaitingRoom.tsx
@@ -18,7 +18,7 @@ export function WaitingRoom({ roomId, players, currentPlayerId, onReady, onLeave
   const canStart = players.length >= 2 && players.every(p => p.isReady);
 
   return (
-    <div className="min-h-screen bg-gradient-to-br from-blue-500 via-purple-500 to-pink-500 flex items-center justify-center p-4">
+    <main className="min-h-screen bg-gradient-to-br from-blue-500 via-purple-500 to-pink-500 flex items-center justify-center p-4" role="main">
       <motion.div
         initial={{ scale: 0.9, opacity: 0 }}
         animate={{ scale: 1, opacity: 1 }}
@@ -102,11 +102,12 @@ export function WaitingRoom({ roomId, players, currentPlayerId, onReady, onLeave
               whileTap={{ scale: 0.98 }}
               onClick={onReady}
               className="w-full bg-gradient-to-r from-green-500 to-green-600 text-white py-3 rounded-lg font-semibold shadow-lg hover:shadow-xl transition-shadow"
+              aria-label="Mark yourself as ready to start the game"
             >
               Ready to Play
             </motion.button>
           ) : (
-            <div className="w-full bg-green-100 border-2 border-green-500 text-green-700 py-3 rounded-lg font-semibold text-center">
+            <div className="w-full bg-green-100 border-2 border-green-500 text-green-700 py-3 rounded-lg font-semibold text-center" role="status" aria-live="polite">
               {canStart ? 'Starting game...' : players.length < 2 ? 'Waiting for at least 1 more player...' : 'Waiting for other players...'}
             </div>
           )}
@@ -116,12 +117,13 @@ export function WaitingRoom({ roomId, players, currentPlayerId, onReady, onLeave
             whileTap={{ scale: 0.98 }}
             onClick={onLeave}
             className="w-full bg-gray-300 text-gray-700 py-3 rounded-lg font-semibold hover:bg-gray-400 transition-colors"
+            aria-label="Leave the waiting room and return to menu"
           >
             Leave Room
           </motion.button>
         </div>
 
-        <div className="mt-6 p-4 bg-blue-50 border border-blue-200 rounded-lg">
+        <div className="mt-6 p-4 bg-blue-50 border border-blue-200 rounded-lg" role="region" aria-label="Game rules">
           <h4 className="font-semibold text-blue-900 mb-2">Game Rules</h4>
           <ul className="text-sm text-blue-800 space-y-1">
             <li>• 2-4 players can play (minimum 2 required)</li>
@@ -132,6 +134,6 @@ export function WaitingRoom({ roomId, players, currentPlayerId, onReady, onLeave
           </ul>
         </div>
       </motion.div>
-    </div>
+    </main>
   );
 }