Simulating AutoNumber field in SQLServer

<img src='https://asprunner.com/forums/file.php?topicimage=1&fieldname=question&id=711&image=1&table=forumtopics' class='bbc_emoticon' alt=':D' /> Hello, is there any body that may know this?
Microsoft Access has those AutoNumber type of fields. How could I increment those number fields that are autoNumber in access that basically are key fields and they are incremented automatically but in SqlServer does not exit or at least don't know how to make it work.
Thanks

Alberto