In this article, a functioning Tic-Tac-Toe program is developed - it might not be the fullest implementation, but it works. The program concentrates on a sensible implementation that might serve as a foundation for possibly more intricate implementations. The following assumes you are familiar with the rules of Tic-Tac-Toe – if not, take a minute to look them up. Also, a basic understanding of C#, WinForms, VS.NET and data structures is assumed.