Prime Directive is a roleplaying system set in the Star Fleet Universe. For this campaign, we’re using GURPS, as it can handle the flexibility of characters who aren’t Star Fleet personnel.
The emphasis is on exploration and discovery, so personal combat is simplified a bit from the GURPS norm. In the event of space combat, groups who enjoy tactical wargames use Star Fleet Battles to resolve the situation, while other groups use an abstracted simulation based on their characters’ skills.
Star Fleet Battles and the Star Fleet Universe are ©Amarillo Design Bureau, Inc. GURPS is ©Steve Jackson Games. Star Trek is ©Parmount Pictures.