Professionalism is a required competency for medical students, residents, practicing physicians, and academic faculty. Faculty members must adhere to codes of conduct or risk discipline. The authors describe issues of unprofessionalism that culminate in allegations of faculty misconduct or filing of grievances in academic medicine and outline strategies for early intervention and prevention. The authors, vice and associate deans and executive director of the office of faculty affairs at a large U.S. medical school, have handled many allegations of unprofessional conduct over the past decade. They present case examples based on behaviors such as lack of respect, inappropriate language and behavior, failure to cooperate with members of the health care team, and sexual harassment/discrimination. They discuss factors complicating evaluation of these behaviors, including variable definitions of respect, different cultural norms, and false allegations. The authors make recommendations for prevention and intervention, including early identification, performance management, education about sexual harassment, and referrals to professional coaches, anger management classes, and faculty–staff assistance programs.