Bruce Mansfield & Jason Carr will discuss the history and principles solitaire tabletop gaming. Solitaire tabletop gaming has exploded in popularity over the last decade, both in solitaire-specific game designs, and solitaire game variants. Why is solitaire gaming becoming more popular? What design considerations are specific to solitaire design? How did we get to this point? This talk will outline the history of solitaire wargaming, analyze various solitaire design mechanisms, and speak about the tradeoffs in usability, complexity, and simulation in solitaire wargame designs, with special attention paid to 'bots' - automated solitaire opponents in otherwise multiplayer games.