When physicians and advanced practice providers behave unprofessionally, they can diminish both individual patient safety and organizational safety culture. Historically, power gradients in health care have led to underreporting of unprofessional provider behavior. Investigators analyzed an anonymous incident reporting system for coworkers, created a taxonomy for unprofessional behavior, and then validated the taxonomy with a group of experts. They classified 120 reports into 4 professionalism domains: competent medical care, clear and respectful communication, responsibility, and integrity. Disrespectful or offensive communication was the most common unprofessional behavior observed. Two previous WebM&M commentaries explored approaches to unprofessional behavior among trainees and attending physicians.