Initially, Fallout was meant to use the GURPS system by Steve Jackson Games. However, there were difficulties in the license that could not be overcome, and so the two companies mutually agreed to end the partnership. Fortunately for the Fallout team, the only element of GURPS in Fallout was the ruleset and the setting was entirely Interplay's, so they could continue development. Chris Taylor, Jesse Heinig and Tim Cain developed the SPECIAL system. Many elements from it are inspired by GURPS, but it is largely original.