diff --git a/proxy/src/main/java/net/md_5/bungee/connection/InitialHandler.java b/proxy/src/main/java/net/md_5/bungee/connection/InitialHandler.java
index 44bc56df..caa61223 100644
--- a/proxy/src/main/java/net/md_5/bungee/connection/InitialHandler.java
+++ b/proxy/src/main/java/net/md_5/bungee/connection/InitialHandler.java
@@ -39,6 +39,7 @@ import net.md_5.bungee.netty.PacketDecoder;
 import net.md_5.bungee.netty.PacketHandler;
 import net.md_5.bungee.netty.PipelineUtils;
 import net.md_5.bungee.protocol.Forge;
+import net.md_5.bungee.protocol.Vanilla;
 import net.md_5.bungee.protocol.packet.DefinedPacket;
 import net.md_5.bungee.protocol.packet.Packet1Login;
 import net.md_5.bungee.protocol.packet.Packet2Handshake;
@@ -142,6 +143,14 @@ public class InitialHandler extends PacketHandler implements PendingConnection
         this.handshake = handshake;
         bungee.getLogger().log( Level.INFO, "{0} has connected", this );
 
+        if ( handshake.getProcolVersion() > Vanilla.PROTOCOL_VERSION )
+        {
+            disconnect( "Outdated server!" );
+        } else if ( handshake.getProcolVersion() < Vanilla.PROTOCOL_VERSION )
+        {
+            disconnect( "Outdated client!" );
+        }
+
         if ( handshake.getUsername().length() > 16 )
         {
             disconnect( "Cannot have username longer than 16 characters" );