to ones that developed the main characters and their relationships, which many point to as the turning point for the series. Another key innovation was Piller’s open-door policy for scripts, allowing anyone to submit story ideas. This policy yielded some of the series’ most popular episodes, including "Yesterday's Enterprise". The Next Generation ran for seven years and garnered increasing critical recognition, culminating in an Emmy Award nomination in its final year for Outstanding Drama Series. Piller was personally responsible for a number of popular episodes, including "The Best of Both Worlds", Parts 1 & 2, which are frequently identified as the best episodes of The Next Generation, and the two-part fifth season "Unification", which saw the appearance of Spock, portrayed by Leonard Nimoy, who originated the role on the original Star Trek series. In late 1991, when The Next Generation executive producer Rick Berman was asked by Paramount Pictures to create a new Star Trek series, he turned to Piller to help him create the new show. Star Trek: Deep Space Nine debuted in January 1993 with "Emissary", the pilot episode written by Piller, to the highest-ever ratings for a syndicated series premiere. Like The Next Generation, the series ran for seven years, with Piller serving as showrunner for its first two seasons. He was succeeded as showrunner on The Next Generation by Jeri Taylor after the series’ fifth season. In 1994, Berman was again asked to create another new Star Trek series for Paramount's new UPN television network. As before, Berman teamed with Piller, developing Star Trek: Voyager along with Taylor. When Voyager began its first season, Piller transferred fully to Voyager and was replaced as showrunner on Deep Space Nine by Ira Steven Behr, who served as showrunner for that series' remaining years. Piller served as showrunner and head of the writing staff for Voyagers first two seasons, with Taylor serving as his deputy. Piller left Voyager and retired from the franchise after its second season with Taylor succeeding him for the third season. At the same time, Piller developed another series for UPN called Legend. the series was cancelled after only 12 episodes. Piller continued as a creative consultant on Deep Space Nine and Voyager, sending in notes on scripts as they were being prepared for production. In 1993, Piller had been approached to write one of two prospective scripts for the first Next Generation feature film,