The original release of Prime Directive was published by Task Force Games in 1993. Using an in-house design by Mark Costello and Timothy D. Olsen, it used a D6-style system similar to Shadowrun and . PD’s most popular aspects were a multi-tiered task resolution system, where characters could achieve 'Complete', 'Moderate', 'Minimal', 'Failure' or 'Botch' levels of success with their actions, and the Character Reputation and Background system that allowed characters to “spontaneously” develop skills, abilities, and prior associations appropriate to the mission at hand. Both of these aspects provided a sense of Television Series verisimilitude that many found to be appropriate to the game’s Trek origins. The greatest complaint was that character selection was limited to members of a Prime Team or a similar group, not allowing players to be captains or other important positions, although later supplements did provide this ability. Also, since the rules were unique to this game, and only vaguely similar to other systems, many players were not willing to take the time and effort required to learn them, although the same could be said of many RPGs of that time. The published books for the game included the core rulebook, a Federation sourcebook. and a few adventure books.
''GURPS Prime Directive''
After the folding of Task Force Games and the cancellation of the original Prime Directive line, Amarillo Design Bureau, Inc., the new publishers of Star Fleet Universe games, were left with the question of what to do with PD. They were primarily a wargame company, and the poorsales of the supplements were cause for a reexamination. Eventually, they approached Steve Jackson Games to utilize the Powered by GURPS format.
''D20 Prime Directive and D20M Prime Directive''
At this writing, the core rulebook, D20 Klingons, D20 Romulans, and D20 Federation are available for this system. Supplements for the Gorns, Tholians and other empires/races are in various writing stages.
''Other Prime Directive variants''
It has been announced that Traveller Prime Directive and related sourcebooks will be released beginning in Spring 2012 in order to further expand the potential user base for the role-playing aspect of the Star Fleet Universe.
Prime Teams
Prime Teams were a concept pioneered in the original Prime Directive game. The concept was a specialized 'Landing Party' that could do a wide variety of functions, including science, negotiations, and combat. The concept was developed by the designers who wished to avoid the television and moviecliché of having the Captain and primary bridge personnel always putting themselves in danger. Prime Teams were criticised by some as being essentially a Star Fleet version of the "adventuring party" found in numerous Dungeons & Dragons-style fantasy games. While "Prime Teams" themselves are a Federation designation, nearly every empire had their own equivalent.
Reception
Chris McCubbin reviewed Prime Directive for Pyramid #7 and stated that "My advice to Star Trek fans interested in Prime Directive is to play it, but play it on its own terms, as a good, solid outer space military adventure, without trying to squeeze it into the TV show's mold in every tiny detail. To tell you the truth, the universe of Prime Directive is much more playable than the Star Trek universe anyway, while preserving most of the elements that got trekkies interested in Star Trek in the first place."
