diff --git a/README.md b/README.md
index bf0f276..5d0984d 100644
--- a/README.md
+++ b/README.md
@@ -14,6 +14,7 @@
 - Automatically rename a file when matching names.
 - Getting file information.
 - Play one or more files.
+- Prevents power sleep on converting.
 
 ## Video conversion
 
diff --git a/SevenConverter/Forms/Main.cs b/SevenConverter/Forms/Main.cs
index ba25d00..15713cb 100644
--- a/SevenConverter/Forms/Main.cs
+++ b/SevenConverter/Forms/Main.cs
@@ -105,6 +105,8 @@ private void BtnStart_Click(object sender, EventArgs e)
 
             if (listSoruceFiles.Items.Count > 0)
             {
+                Tools.PreventSleep();
+
                 if (!String.IsNullOrEmpty(tbDestFilePath.Text)
                     && !Directory.Exists(tbDestFilePath.Text))
                 {
@@ -158,6 +160,8 @@ private void BtnStart_Click(object sender, EventArgs e)
                     // done!
                     if (result)
                         SystemSounds.Exclamation.Play();
+
+                    Tools.AllowSleep();
                 }
                 else
                     MessageBox.Show(Properties.strings.FolderDoesNotExist,
diff --git a/SevenConverter/Properties/AssemblyInfo.cs b/SevenConverter/Properties/AssemblyInfo.cs
index 346d773..83acaf8 100644
--- a/SevenConverter/Properties/AssemblyInfo.cs
+++ b/SevenConverter/Properties/AssemblyInfo.cs
@@ -31,5 +31,5 @@
 // You can specify all the values or you can default the Build and Revision Numbers
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("1.5.5.0")]
-[assembly: AssemblyFileVersion("1.5.5.0")]
\ No newline at end of file
+[assembly: AssemblyVersion("1.5.6.0")]
+[assembly: AssemblyFileVersion("1.5.6.0")]
\ No newline at end of file
diff --git a/SevenConverter/Utils/Tools.cs b/SevenConverter/Utils/Tools.cs
index 65d8239..959acee 100644
--- a/SevenConverter/Utils/Tools.cs
+++ b/SevenConverter/Utils/Tools.cs
@@ -1,4 +1,6 @@
-using System.Reflection;
+using System;
+using System.Reflection;
+using System.Runtime.InteropServices;
 using System.Threading;
 using System.Windows.Forms;
 
@@ -6,11 +8,34 @@ namespace SevenConverter.Utils
 {
     public static class Tools
     {
+        [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
+        private static extern ExecutionState SetThreadExecutionState(ExecutionState esFlags);
+
+        [FlagsAttribute]
+        private enum ExecutionState : uint
+        {
+            EsAwaymodeRequired = 0x00000040,
+            EsContinuous = 0x80000000,
+            EsDisplayRequired = 0x00000002,
+            EsSystemRequired = 0x00000001
+        }
+
+        public static void PreventSleep()
+        {
+            SetThreadExecutionState(ExecutionState.EsContinuous | ExecutionState.EsSystemRequired);
+        }
+
+        public static void AllowSleep()
+        {
+            SetThreadExecutionState(ExecutionState.EsContinuous);
+        }
+
         public static string GetProgramVersion()
         {
             return Assembly.GetExecutingAssembly().GetName().Version.ToString();
         }
 
+
         public static void ShowPanel(Control toggleControl, Panel panel, bool show, int height)
         {
             panel.Left = toggleControl.Left + toggleControl.Width;