This article examines the social organization of informal discussions between defense and prosecution lawyers that result in a defendant’s decision to plead guilty. In-depth, semi-structured interviews with legal practitioners and members of the judiciary in Australia demonstrate the ways in which participants in plea discussions understand and justify their respective involvement (or lack of it) and simultaneously attempt to demarcate some tasks as legitimate legal work and, therefore, as outside the jurisdiction of other occupations within the criminal justice process. Legal practitioners’ accounts emphasized that, because there is no judicial involvement in plea discussions, the type or length of the actual sentence could not be guaranteed. This, they claimed, avoids the coerciveness of judicial plea bargaining. Second, they stressed that it is the defendant’s decision whether to plead guilty, thus affirming the rhetoric of voluntariness. These accounts are components of professional boundary maintenance: claims that certain practices, tasks, and responsibilities are legitimate legal work and, therefore, should be performed exclusively by legal personnel. This is an important strategy in asserting professional dominance, especially when lawyers are highly dependent on the police and the courts.