From ADB's perspective:
To clarfiy, the way PD has worked is to share (mostly) the same background information across the various game systems, and to tailor the rule-specific details for each engine as required. Thus, GURPS Federation and PD20M Federation have the same fluff, but have different rules for actually writing up your characters. (Only the core PD rulebooks vary background-wise; the GURPS edition includes a few extra details, such as the five founding ISC species. Plus it has a basic version of the 4th ed GURPS ruleset included, while the D20M version requires you to use a separate game ruleset.)PRIME DIRECTIVE: TRAVELLER
One of the most popular RPG game engines in the industry is the Traveller series (produced, in various incarnations, by Game Designer’s Workshop and Steve Jackson Games), and the current “Mongoose Traveller” incarnation is the most successful ever. They have an “open license” and Jean Sexton’s team was already at work doing a Prime Directive Traveller version for that system. Our experiences with GURPS, however, showed that any RPG done by a publisher other than the original will have at most 10% of the sales of books by the original publisher. (Hence, our GURPS books are done to the design standard of SJG books, but sell only a fraction of the numbers.) Doing these books as a joint venture means every retailer will carry them.