diff --git a/src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/Client.java b/src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/Client.java
index a4f5127..98e7232 100644
--- a/src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/Client.java
+++ b/src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/Client.java
@@ -2,7 +2,6 @@ package ch.unibas.dmi.dbis.cs108.multiplayer.client;
 
 import ch.unibas.dmi.dbis.cs108.multiplayer.helpers.ClientPinger;
 
-
 import java.net.Socket;
 import java.io.*;
 import java.net.UnknownHostException;
diff --git a/src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/server/ClientHandler.java b/src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/server/ClientHandler.java
index 6b204bf..5c072cf 100644
--- a/src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/server/ClientHandler.java
+++ b/src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/server/ClientHandler.java
@@ -29,6 +29,12 @@ public class ClientHandler implements Runnable {
       this.out = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
       this.in = new BufferedReader((new InputStreamReader((socket.getInputStream()))));
       this.clientUserName = in.readLine();
+      // duplicate handling: if username already taken, assign random name to client
+      if (AllClientNames.allNames("").contains(clientUserName)) {
+        clientUserName = NameGenerator.randomName();
+      }
+      // add username to list of all client names for future duplicate checking
+      AllClientNames.allNames(clientUserName);
       connectedClients.add(this);
       serverPinger = new ServerPinger(out, socket);
       Thread sP = new Thread(serverPinger);
diff --git a/src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/NameGenerator.java b/src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/server/NameGenerator.java
similarity index 90%
rename from src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/NameGenerator.java
rename to src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/server/NameGenerator.java
index 7ec6886..2739cf7 100644
--- a/src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/NameGenerator.java
+++ b/src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/server/NameGenerator.java
@@ -1,4 +1,4 @@
-package ch.unibas.dmi.dbis.cs108.multiplayer.client;
+package ch.unibas.dmi.dbis.cs108.multiplayer.server;
 
 import java.util.Random;