Psychiatrists and nonphysician mental health professionals working in community mental health centers have difficulty establishing the scope of their expertise, defining the limits of their roles, delegating responsibility, and sharing professional liability. The clinical, political, and administrative aspects of these tensions are examined in the context of arguments for and against physicians' delegating to nonphysician mental health professionals the task of screening CMHC patients for tardive dyskinesia using the Abnormal Involuntary Movement Scale. In 43 percent of mental health centers in Massachusetts surveyed by the authors, nonphysicians perform tardive dyskinesia screening. The authors suggest that the benefits of involving nonphysicians in tardive dyskinesia screening in the CMHC setting outweight the disadvantages.