I. F. Stone has never loomed larger as a role model for American journalists than he does now. Yet since his death in 1989, persistent allegations have surfaced about associations he may have had with Soviet intelligence. The Vassiliev notebooks shed important new light on this question, although definitive answers remain elusive. The notebooks show that Stone did actively cooperate with Soviet intelligence in the mid-to-late 1930s. They leave unclear whether he also maintained a furtive relationship in the 1950s. Evidence suggests that Stone's only active period of cooperation was in the 1930s.