Is your organisation still running Windows Server 2003? With end of support approaching (326 days, 9 hours and 44 minutes to be exact), you may be starting to look at your options.
You can start to plan your migration with the Microsoft Migration Planning Assistant. There is also a host of other datasheets and resources on the Windows Server 2003 page.
Microsoft Virtual Academy has also recently launched a new course covering the migration off Windows Server 2003 with AppZero. They discuss upgrading to Windows Server 2012 R2 and the migration to Microsoft Azure. It is a relatively short course, but a great start in planning your migration off Windows Server 2003.