diff --git a/com/javadevjournal/design/behavioral/observer/FirstSubscriber.java b/com/javadevjournal/design/behavioral/observer/FirstSubscriber.java
new file mode 100644
index 0000000..7862c2a
--- /dev/null
+++ b/com/javadevjournal/design/behavioral/observer/FirstSubscriber.java
@@ -0,0 +1,8 @@
+package main.com.kunwar.designpatterns.behavioral.observer;
+
+public class FirstSubscriber implements IObserver {
+    @Override
+    public void update(Update m) {
+        System.out.println("MessageSubscriberOne :: " + m.getMessageContent());
+    }
+}
\ No newline at end of file
diff --git a/com/javadevjournal/design/behavioral/observer/IObserver.java b/com/javadevjournal/design/behavioral/observer/IObserver.java
new file mode 100644
index 0000000..2ff2a2f
--- /dev/null
+++ b/com/javadevjournal/design/behavioral/observer/IObserver.java
@@ -0,0 +1,5 @@
+package main.com.kunwar.designpatterns.behavioral.observer;
+
+public interface IObserver {
+    public void update(Update m);
+}
\ No newline at end of file
diff --git a/com/javadevjournal/design/behavioral/observer/ISubject.java b/com/javadevjournal/design/behavioral/observer/ISubject.java
new file mode 100644
index 0000000..d04ec27
--- /dev/null
+++ b/com/javadevjournal/design/behavioral/observer/ISubject.java
@@ -0,0 +1,7 @@
+package main.com.kunwar.designpatterns.behavioral.observer;
+
+public interface ISubject {
+    public void attach(IObserver o);
+    public void detach(IObserver o);
+    public void notifyUpdate(Update m);
+}
\ No newline at end of file
diff --git a/com/javadevjournal/design/behavioral/observer/MessagePublisher.java b/com/javadevjournal/design/behavioral/observer/MessagePublisher.java
new file mode 100644
index 0000000..5650c56
--- /dev/null
+++ b/com/javadevjournal/design/behavioral/observer/MessagePublisher.java
@@ -0,0 +1,28 @@
+package main.com.kunwar.designpatterns.behavioral.observer;
+
+import java.util.ArrayList;
+import java.util.List;
+ 
+public class MessagePublisher implements ISubject {
+     
+    private List<IObserver> observers = new ArrayList<>();
+
+    ////in multithreaded environment, please use thread-safe collections
+    @Override
+    public void attach(IObserver o) {
+        observers.add(o);
+    }
+
+    //in multithreaded environment, please use thread-safe collections
+    @Override
+    public void detach(IObserver o) {
+        observers.remove(o);
+    }
+ 
+    @Override
+    public void notifyUpdate(Update m) {
+        for(IObserver o: observers) {
+            o.update(m);
+        }
+    }
+}
\ No newline at end of file
diff --git a/com/javadevjournal/design/behavioral/observer/ObserverPatternDemo.java b/com/javadevjournal/design/behavioral/observer/ObserverPatternDemo.java
new file mode 100644
index 0000000..bb2a2a5
--- /dev/null
+++ b/com/javadevjournal/design/behavioral/observer/ObserverPatternDemo.java
@@ -0,0 +1,22 @@
+package main.com.kunwar.designpatterns.behavioral.observer;
+
+public class ObserverPatternDemo {
+
+    public static void main(String[] args) {
+        FirstSubscriber firstSubscriber = new FirstSubscriber();
+        SecondSubscriber secondSubscriber = new SecondSubscriber();
+        ThirdSubscriber thirdSubscriber = new ThirdSubscriber();
+         
+        MessagePublisher p = new MessagePublisher();
+
+        p.attach(firstSubscriber);
+        p.attach(secondSubscriber);
+         
+        p.notifyUpdate(new Update("This is the first update"));   //s1 and s2 will receive the update
+         
+        p.detach(firstSubscriber);
+        p.attach(thirdSubscriber);
+         
+        p.notifyUpdate(new Update("This is the second update")); //s2 and s3 will receive the update
+    }
+}
\ No newline at end of file
diff --git a/com/javadevjournal/design/behavioral/observer/SecondSubscriber.java b/com/javadevjournal/design/behavioral/observer/SecondSubscriber.java
new file mode 100644
index 0000000..2ec0202
--- /dev/null
+++ b/com/javadevjournal/design/behavioral/observer/SecondSubscriber.java
@@ -0,0 +1,8 @@
+package main.com.kunwar.designpatterns.behavioral.observer;
+
+public class SecondSubscriber implements IObserver {
+    @Override
+    public void update(Update m) {
+        System.out.println("MessageSubscriberTwo :: " + m.getMessageContent());
+    }
+}
diff --git a/com/javadevjournal/design/behavioral/observer/ThirdSubscriber.java b/com/javadevjournal/design/behavioral/observer/ThirdSubscriber.java
new file mode 100644
index 0000000..540b311
--- /dev/null
+++ b/com/javadevjournal/design/behavioral/observer/ThirdSubscriber.java
@@ -0,0 +1,8 @@
+package main.com.kunwar.designpatterns.behavioral.observer;
+
+public class ThirdSubscriber implements IObserver {
+    @Override
+    public void update(Update m) {
+        System.out.println("MessageSubscriberThree :: " + m.getMessageContent());
+    }
+}
\ No newline at end of file
diff --git a/com/javadevjournal/design/behavioral/observer/Update.java b/com/javadevjournal/design/behavioral/observer/Update.java
new file mode 100644
index 0000000..681b48d
--- /dev/null
+++ b/com/javadevjournal/design/behavioral/observer/Update.java
@@ -0,0 +1,13 @@
+package main.com.kunwar.designpatterns.behavioral.observer;
+
+public class Update {
+    final String messageContent;
+     
+    public Update(String m) {
+        this.messageContent = m;
+    }
+ 
+    public String getMessageContent() {
+        return messageContent;
+    }
+}
\ No newline at end of file