For more than a decade, dialysis units have had to contend with an increasing number of difficult or disruptive dialysis patients. These individuals present a spectrum of behaviors, ranging from those that harm only themselves to those that physically endanger dialysis staff. Such behaviors can interfere with the ability of the dialysis staff to care for the patient in question and for other patients; in addition, threats or actual physical abuse jeopardize the health and safety of both patients and staff. In this Review, we discuss how the application of ethical principles can assist dialysis staff to balance their ethical obligations to disruptive and difficult patients with those to other patients and staff, and to establish policies and strategies for the treatment of these challenging patients. This approach also allows health-care professionals to identify the limited situations in which involuntary patient discharge from a dialysis unit is ethically justified.