Teaching hospitals increasingly face challenges with training the next generation of providers while also balancing the need for supervision, autonomy, and safe patient care. Recent recommendations from the Accreditation Council for Graduate Medical Education are expected to take effect in July 2011, and one of those recommendations emphasizes enhanced supervision of early-stage trainees. This study assessed trainee perceptions of failed supervision to better understand the issues and opportunities for prevention. More than 25% of surveyed trainees witnessed a failure of supervision, which were categorized into three types—monitoring, guidance, and feedback. Supervisors' failure to respond to trainees seeking guidance and the trainees' failure themselves to seek such support were highlighted. The authors explore their findings in the context of a call for new educational paradigms, establishing a culture of safety, and management of disruptive behavior.