diff --git a/logs/app.log b/logs/app.log
new file mode 100644
index 00000000..b07b8a71
--- /dev/null
+++ b/logs/app.log
@@ -0,0 +1,40 @@
+INFO core.basesyntax.Counter:18  Before decrementing, Thread #  1, counter value 20
+INFO core.basesyntax.Counter:21   After decrementing, Thread #  1, counter value 19
+INFO core.basesyntax.Counter:18  Before decrementing, Thread #  2, counter value 19
+INFO core.basesyntax.Counter:21   After decrementing, Thread #  2, counter value 18
+INFO core.basesyntax.Counter:18  Before decrementing, Thread #  3, counter value 18
+INFO core.basesyntax.Counter:21   After decrementing, Thread #  3, counter value 17
+INFO core.basesyntax.Counter:18  Before decrementing, Thread #  4, counter value 17
+INFO core.basesyntax.Counter:21   After decrementing, Thread #  4, counter value 16
+INFO core.basesyntax.Counter:18  Before decrementing, Thread #  5, counter value 16
+INFO core.basesyntax.Counter:21   After decrementing, Thread #  5, counter value 15
+INFO core.basesyntax.Counter:18  Before decrementing, Thread #  6, counter value 15
+INFO core.basesyntax.Counter:21   After decrementing, Thread #  6, counter value 14
+INFO core.basesyntax.Counter:18  Before decrementing, Thread #  7, counter value 14
+INFO core.basesyntax.Counter:21   After decrementing, Thread #  7, counter value 13
+INFO core.basesyntax.Counter:18  Before decrementing, Thread #  8, counter value 13
+INFO core.basesyntax.Counter:21   After decrementing, Thread #  8, counter value 12
+INFO core.basesyntax.Counter:18  Before decrementing, Thread #  9, counter value 12
+INFO core.basesyntax.Counter:21   After decrementing, Thread #  9, counter value 11
+INFO core.basesyntax.Counter:18  Before decrementing, Thread # 10, counter value 11
+INFO core.basesyntax.Counter:21   After decrementing, Thread # 10, counter value 10
+INFO core.basesyntax.Counter:18  Before decrementing, Thread # 11, counter value 10
+INFO core.basesyntax.Counter:21   After decrementing, Thread # 11, counter value  9
+INFO core.basesyntax.Counter:18  Before decrementing, Thread # 12, counter value  9
+INFO core.basesyntax.Counter:21   After decrementing, Thread # 12, counter value  8
+INFO core.basesyntax.Counter:18  Before decrementing, Thread # 13, counter value  8
+INFO core.basesyntax.Counter:21   After decrementing, Thread # 13, counter value  7
+INFO core.basesyntax.Counter:18  Before decrementing, Thread # 14, counter value  7
+INFO core.basesyntax.Counter:21   After decrementing, Thread # 14, counter value  6
+INFO core.basesyntax.Counter:18  Before decrementing, Thread # 15, counter value  6
+INFO core.basesyntax.Counter:21   After decrementing, Thread # 15, counter value  5
+INFO core.basesyntax.Counter:18  Before decrementing, Thread # 16, counter value  5
+INFO core.basesyntax.Counter:21   After decrementing, Thread # 16, counter value  4
+INFO core.basesyntax.Counter:18  Before decrementing, Thread # 17, counter value  4
+INFO core.basesyntax.Counter:21   After decrementing, Thread # 17, counter value  3
+INFO core.basesyntax.Counter:18  Before decrementing, Thread # 18, counter value  3
+INFO core.basesyntax.Counter:21   After decrementing, Thread # 18, counter value  2
+INFO core.basesyntax.Counter:18  Before decrementing, Thread # 19, counter value  2
+INFO core.basesyntax.Counter:21   After decrementing, Thread # 19, counter value  1
+INFO core.basesyntax.Counter:18  Before decrementing, Thread # 20, counter value  1
+INFO core.basesyntax.Counter:21   After decrementing, Thread # 20, counter value  0
diff --git a/src/main/java/core/basesyntax/Counter.java b/src/main/java/core/basesyntax/Counter.java
index 4af46bd4..ec73314e 100644
--- a/src/main/java/core/basesyntax/Counter.java
+++ b/src/main/java/core/basesyntax/Counter.java
@@ -1,22 +1,23 @@
 package core.basesyntax;
 
+import java.util.concurrent.atomic.AtomicInteger;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
 public class Counter {
     private static final Logger logger = LogManager.getLogger(Counter.class);
     private static final String MESSAGE = "%20s, Thread # %2s, counter value %2d";
-    private int value;
+    private AtomicInteger value;
 
-    public Counter(int value) {
+    public Counter(AtomicInteger value) {
         this.value = value;
     }
 
-    public void decreaseValue() {
+    public synchronized void decreaseValue() {
         logger.info(String.format(MESSAGE,
-                "Before decrementing", Thread.currentThread().getName(), value));
-        value--;
+                "Before decrementing", Thread.currentThread().getName(), value.get()));
+        value.decrementAndGet();
         logger.info(String.format(MESSAGE,
-                "After decrementing", Thread.currentThread().getName(), value));
+                    "After decrementing", Thread.currentThread().getName(), value.get()));
     }
 }
diff --git a/src/main/java/core/basesyntax/Main.java b/src/main/java/core/basesyntax/Main.java
index 48a2c730..3c8462b2 100644
--- a/src/main/java/core/basesyntax/Main.java
+++ b/src/main/java/core/basesyntax/Main.java
@@ -1,10 +1,24 @@
 package core.basesyntax;
 
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
+
 public class Main {
-    public static void main(String[] args) {
-        Counter counter = new Counter(20);
+    public static void main(String[] args) throws InterruptedException {
+        Counter counter = new Counter(new AtomicInteger(20));
+        List<MyThread> threads = new ArrayList<>();
         for (int i = 1; i <= 20; i++) {
-            new MyThread(counter, String.valueOf(i)).start();
+            threads.add(new MyThread(counter, String.valueOf(i)));
+        }
+
+        for (MyThread thread : threads) {
+            thread.start();
+            try {
+                Thread.sleep(200);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
         }
     }
 }