diff --git a/src/main/java/ru/windcorp/progressia/server/comms/ClientManager.java b/src/main/java/ru/windcorp/progressia/server/comms/ClientManager.java
index 6ab3852..1796977 100644
--- a/src/main/java/ru/windcorp/progressia/server/comms/ClientManager.java
+++ b/src/main/java/ru/windcorp/progressia/server/comms/ClientManager.java
@@ -5,6 +5,7 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.concurrent.atomic.AtomicInteger;
 
+import glm.vec._3.i.Vec3i;
 import gnu.trove.TCollections;
 import gnu.trove.map.TIntObjectMap;
 import gnu.trove.map.hash.TIntObjectHashMap;
@@ -68,6 +69,10 @@ public class ClientManager {
 		getServer().getPlayerManager().getPlayers().add(player);
 		
 		for (ChunkData chunk : server.getWorld().getData().getChunks()) {
+			if (!client.canSeeChunk(chunk.getPosition())) {
+				continue;
+			}
+			
 			PacketLoadChunk packet = new PacketLoadChunk("Core:LoadChunk");
 			packet.getPosition().set(
 					chunk.getPosition().x,
@@ -91,7 +96,11 @@ public class ClientManager {
 		clientsById.remove(client.getId());
 	}
 	
-	public void broadcastGamePacket(Packet packet) {
+	/**
+	 * Sends the provided packet to all connected player clients.
+	 * @param packet the packet to broadcast
+	 */
+	public void broadcastToAllPlayers(Packet packet) {
 		getClients().forEach(c -> {
 				if (c.getState() != State.CONNECTED) return;
 				if (!(c instanceof ClientPlayer)) return;
@@ -99,6 +108,34 @@ public class ClientManager {
 		});
 	}
 	
+	/**
+	 * Sends the provided packet to all connected player clients that can see the chunk identified by {@code chunkPos}.
+	 * @param packet the packet to broadcast
+	 * @param chunkPos the chunk coordinates of the chunk that must be visible
+	 */
+	public void broadcastLocal(Packet packet, Vec3i chunkPos) {
+		getClients().forEach(c -> {
+				if (c.getState() != State.CONNECTED) return;
+				if (!(c instanceof ClientPlayer)) return;
+				if (!((ClientPlayer) c).canSeeChunk(chunkPos)) return;
+				c.sendPacket(packet);
+		});
+	}
+	
+	/**
+	 * Sends the provided packet to all connected player clients that can see the entity identified by {@code entityId}.
+	 * @param packet the packet to broadcast
+	 * @param entityId the ID of the entity that must be visible
+	 */
+	public void broadcastLocal(Packet packet, long entityId) {
+		getClients().forEach(c -> {
+				if (c.getState() != State.CONNECTED) return;
+				if (!(c instanceof ClientPlayer)) return;
+				if (!((ClientPlayer) c).canSeeEntity(entityId)) return;
+				c.sendPacket(packet);
+		});
+	}
+	
 	public Collection<Client> getClients() {
 		return clients;
 	}
diff --git a/src/main/java/ru/windcorp/progressia/server/comms/ClientPlayer.java b/src/main/java/ru/windcorp/progressia/server/comms/ClientPlayer.java
index 3eb14e1..d49addd 100644
--- a/src/main/java/ru/windcorp/progressia/server/comms/ClientPlayer.java
+++ b/src/main/java/ru/windcorp/progressia/server/comms/ClientPlayer.java
@@ -1,5 +1,8 @@
 package ru.windcorp.progressia.server.comms;
 
+import glm.vec._3.i.Vec3i;
+import ru.windcorp.progressia.test.TestContent;
+
 public abstract class ClientPlayer extends Client {
 
 	public ClientPlayer(int id) {
@@ -7,5 +10,13 @@ public abstract class ClientPlayer extends Client {
 	}
 	
 	public abstract String getLogin();
+	
+	public boolean canSeeChunk(Vec3i chunkPos) {
+		return true;
+	}
+	
+	public boolean canSeeEntity(long entityId) {
+		return entityId == TestContent.PLAYER_ENTITY_ID;
+	}
 
 }
diff --git a/src/main/java/ru/windcorp/progressia/server/world/tasks/AddTile.java b/src/main/java/ru/windcorp/progressia/server/world/tasks/AddTile.java
index 4402999..28d4558 100644
--- a/src/main/java/ru/windcorp/progressia/server/world/tasks/AddTile.java
+++ b/src/main/java/ru/windcorp/progressia/server/world/tasks/AddTile.java
@@ -45,6 +45,12 @@ class AddTile extends CachedWorldChange {
 		Coordinates.convertInWorldToChunk(blockInWorld, output);
 	}
 	
+	@Override
+	protected Vec3i getAffectedChunk(Vec3i output) {
+		getRelevantChunk(output);
+		return output;
+	}
+	
 	@Override
 	public void dispose() {
 		super.dispose();
diff --git a/src/main/java/ru/windcorp/progressia/server/world/tasks/CachedWorldChange.java b/src/main/java/ru/windcorp/progressia/server/world/tasks/CachedWorldChange.java
index be587f8..ee965c7 100644
--- a/src/main/java/ru/windcorp/progressia/server/world/tasks/CachedWorldChange.java
+++ b/src/main/java/ru/windcorp/progressia/server/world/tasks/CachedWorldChange.java
@@ -2,7 +2,9 @@ package ru.windcorp.progressia.server.world.tasks;
 
 import java.util.function.Consumer;
 
+import glm.vec._3.i.Vec3i;
 import ru.windcorp.progressia.common.comms.packets.PacketWorldChange;
+import ru.windcorp.progressia.common.util.Vectors;
 import ru.windcorp.progressia.common.world.WorldData;
 import ru.windcorp.progressia.server.Server;
 
@@ -24,7 +26,21 @@ public abstract class CachedWorldChange extends CachedChange {
 	@Override
 	public void affect(Server server) {
 		affectCommon(server.getWorld().getData());
-		server.getClientManager().broadcastGamePacket(packet);
+		
+		Vec3i v = Vectors.grab3i();
+		Vec3i chunkPos = getAffectedChunk(v);
+		
+		if (chunkPos == null) {
+			server.getClientManager().broadcastToAllPlayers(packet);
+		} else {
+			server.getClientManager().broadcastLocal(packet, chunkPos);
+		}
+		
+		Vectors.release(chunkPos);
+	}
+	
+	protected Vec3i getAffectedChunk(Vec3i output) {
+		return null;
 	}
 	
 	/**
diff --git a/src/main/java/ru/windcorp/progressia/server/world/tasks/ChangeEntity.java b/src/main/java/ru/windcorp/progressia/server/world/tasks/ChangeEntity.java
index f671914..651bc83 100644
--- a/src/main/java/ru/windcorp/progressia/server/world/tasks/ChangeEntity.java
+++ b/src/main/java/ru/windcorp/progressia/server/world/tasks/ChangeEntity.java
@@ -50,7 +50,7 @@ class ChangeEntity extends CachedChange {
 			CrashReports.report(e, "Could not write entity %s", entity);
 		}
 		
-		server.getClientManager().broadcastGamePacket(packet);
+		server.getClientManager().broadcastLocal(packet, entity.getChunkCoords(null));
 	}
 	
 	@Override
diff --git a/src/main/java/ru/windcorp/progressia/server/world/tasks/RemoveTile.java b/src/main/java/ru/windcorp/progressia/server/world/tasks/RemoveTile.java
index 7601a83..d33f80f 100644
--- a/src/main/java/ru/windcorp/progressia/server/world/tasks/RemoveTile.java
+++ b/src/main/java/ru/windcorp/progressia/server/world/tasks/RemoveTile.java
@@ -40,5 +40,11 @@ class RemoveTile extends CachedWorldChange {
 	public void getRelevantChunk(Vec3i output) {
 		Coordinates.convertInWorldToChunk(blockInWorld, output);
 	}
+	
+	@Override
+	protected Vec3i getAffectedChunk(Vec3i output) {
+		getRelevantChunk(output);
+		return output;
+	}
 
 }
\ No newline at end of file
diff --git a/src/main/java/ru/windcorp/progressia/server/world/tasks/SetBlock.java b/src/main/java/ru/windcorp/progressia/server/world/tasks/SetBlock.java
index f34694c..44329ac 100644
--- a/src/main/java/ru/windcorp/progressia/server/world/tasks/SetBlock.java
+++ b/src/main/java/ru/windcorp/progressia/server/world/tasks/SetBlock.java
@@ -36,6 +36,12 @@ class SetBlock extends CachedWorldChange {
 		Coordinates.convertInWorldToChunk(blockInWorld, output);
 	}
 	
+	@Override
+	protected Vec3i getAffectedChunk(Vec3i output) {
+		getRelevantChunk(output);
+		return output;
+	}
+	
 	@Override
 	public void dispose() {
 		super.dispose();
diff --git a/src/main/java/ru/windcorp/progressia/test/TestChunkSender.java b/src/main/java/ru/windcorp/progressia/test/TestChunkSender.java
index 672db8f..801c3d8 100644
--- a/src/main/java/ru/windcorp/progressia/test/TestChunkSender.java
+++ b/src/main/java/ru/windcorp/progressia/test/TestChunkSender.java
@@ -37,7 +37,7 @@ public class TestChunkSender implements WorldDataListener {
 			CrashReports.report(e, "TestChunkSender fjcked up. javahorse stupid");
 		}
 		
-		server.getClientManager().broadcastGamePacket(packet);
+		server.getClientManager().broadcastLocal(packet, chunk.getPosition());
 		
 		tmp_sendPlayerIfPossible(world, chunk);
 	}
@@ -48,7 +48,7 @@ public class TestChunkSender implements WorldDataListener {
 		
 		if (Glm.equals(e.getChunkCoords(null), chunk.getPosition())) {
 			System.out.printf("TestChunkSender: player found in (%d; %d; %d)\n", e.getChunkCoords(null).x, e.getChunkCoords(null).y, e.getChunkCoords(null).z);
-			server.getClientManager().broadcastGamePacket(new PacketSetLocalPlayer(e.getEntityId()));
+			server.getClientManager().broadcastToAllPlayers(new PacketSetLocalPlayer(e.getEntityId()));
 		}
 	}