diff --git a/src/main/java/org/fungover/haze/Main.java b/src/main/java/org/fungover/haze/Main.java
index 74e38fa1..f53c2579 100644
--- a/src/main/java/org/fungover/haze/Main.java
+++ b/src/main/java/org/fungover/haze/Main.java
@@ -8,6 +8,7 @@
 import java.io.InputStreamReader;
 import java.net.InetSocketAddress;
 import java.net.ServerSocket;
+import java.net.Socket;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
@@ -19,9 +20,12 @@ public class Main {
     public static void main(String[] args) {
         Initialize initialize = new Initialize();
         initialize.importCliOptions(args);
-
-        HazeDatabase hazeDatabase = new HazeDatabase();
         HazeList hazeList = new HazeList();
+        HazeDatabase hazeDatabase = new HazeDatabase();
+        Auth auth = new Auth();
+        initializeServer(args, initialize, auth);
+        final boolean isPasswordSet = auth.isPasswordSet();
+
 
         Thread printingHook = new Thread(() -> shutdown(hazeDatabase));
         Runtime.getRuntime().addShutdownHook(printingHook);
@@ -36,18 +40,22 @@ public static void main(String[] args) {
                 Runnable newThread = () -> {
                     try {
                         BufferedReader input = new BufferedReader(new InputStreamReader(client.getInputStream()));
-
+                        boolean clientAuthenticated = false;
                         while (true) {
                             List<String> inputList = new ArrayList<>();
 
                             String firstReading = input.readLine();
                             readInputStream(input, inputList, firstReading);
 
-                            client.getOutputStream().write(executeCommand(hazeDatabase, inputList,hazeList ).getBytes());
+                            clientAuthenticated = authenticateClient(auth, isPasswordSet, client, inputList, clientAuthenticated);
+
+                            client.getOutputStream().write(executeCommand(hazeDatabase, inputList, hazeList).getBytes());
 
                             inputList.forEach(System.out::println); // For checking incoming message
 
                             printThreadDebug();
+
+                            inputList.clear();
                         }
 
                     } catch (IOException e) {
@@ -73,7 +81,7 @@ private static void printThreadDebug() {
     }
 
     public static String executeCommand(HazeDatabase hazeDatabase, List<String> inputList, HazeList hazeList) {
-        logger.debug("executeCommand: {} {} ", ()->  hazeDatabase, ()-> inputList);
+        logger.debug("executeCommand: {} {} ", () -> hazeDatabase, () -> inputList);
         String command = inputList.get(0).toUpperCase();
 
         return switch (command) {
@@ -91,13 +99,14 @@ public static String executeCommand(HazeDatabase hazeDatabase, List<String> inpu
             case "LLEN" -> hazeList.lLen(inputList);
             case "LMOVE" -> hazeList.lMove(inputList);
             case "LTRIM" -> hazeList.callLtrim(inputList);
+            case "AUTH" -> "+OK\r\n";
             default -> "-ERR unknown command\r\n";
         };
     }
 
     private static void readInputStream(BufferedReader input, List<String> inputList, String firstReading) throws
             IOException {
-        logger.debug("readInputStream: {} {} {}", ()-> input, () ->  inputList, () -> firstReading);
+        logger.debug("readInputStream: {} {} {}", () -> input, () -> inputList, () -> firstReading);
         int size;
         if (firstReading.startsWith("*")) {
             size = Integer.parseInt(firstReading.substring(1)) * 2;
@@ -112,4 +121,27 @@ private static void readInputStream(BufferedReader input, List<String> inputList
         }
     }
 
+    private static void initializeServer(String[] args, Initialize initialize, Auth auth) {
+        initialize.importCliOptions(args);
+        auth.setPassword(initialize.getPassword());
+    }
+
+    private static boolean authenticateClient(Auth auth, boolean isPasswordSet, Socket client, List<String> inputList, boolean clientAuthenticated) throws IOException {
+        if (authCommandReceived(isPasswordSet, inputList, clientAuthenticated))
+            return auth.authenticate(inputList.get(1), client);
+
+        shutdownClientIfNotAuthenticated(client, clientAuthenticated, isPasswordSet);
+        return clientAuthenticated;
+    }
+
+    private static void shutdownClientIfNotAuthenticated(Socket client, boolean clientAuthenticated, boolean isPasswordSet) throws IOException {
+        if (!clientAuthenticated && isPasswordSet) {
+            client.getOutputStream().write(Auth.printAuthError());
+            client.shutdownOutput();
+        }
+    }
+
+    private static boolean authCommandReceived(boolean isPasswordSet, List<String> inputList, boolean clientAuthenticated) {
+        return isPasswordSet && !clientAuthenticated && inputList.size() == 2 && inputList.get(0).equals("AUTH");
+    }
 }