Approximately 10%–30% of patients treated in health care settings exhibit difficult behavior,^{[1], [2] and [3]} although the specific frequency of difficult patient encounters in oncology practices is unknown. Difficult behavior takes many forms in the cancer setting: arriving late or not showing to appointments, intense questioning of the clinician, frequent pages or e-mails between appointments, and angry or demanding behavior toward staff and clinicians. Difficult patients tend to evoke negative emotions, such as guilt, irritation, anxiety, and aversion, in the clinician. They often have difficulties forming effective treatment alliances with both medical and mental health providers and may exhibit treatment nonadherence and high resource utilization. Although most cancer patients with high levels of psychological distress benefit significantly from supportive counseling with a mental health clinician, either difficult patients refuse referrals or their emotional symptoms are refractory to usual therapeutic interventions and medication management. Some difficult patients may even threaten legal action because of perceived medical negligence or improper treatment.⁴ Many, but not all, difficult patients have personality disorders; cultural differences, other psychiatric disorders, circumstances, and relational styles can also manifest themselves as difficult behavior. Physician (or clinician) factors, as well as the challenges and frustrations of negotiating the health care system, may also contribute to patients' difficult behaviors in the health care setting.