Eating disorders are life-threatening conditions that are challenging to address; however, the primary care setting provides an important opportunity for critical medical and psychosocial intervention. The recently published Diagnostic and Statistical Manual of Mental Disorders, 5th ed., includes updated diagnostic criteria for anorexia nervosa (e.g., elimination of amenorrhea as a diagnostic criterion) and for bulimia nervosa (e.g., criterion for frequency of binge episodes decreased to an average of once per week). In addition to the role of environmental triggers and societal expectations of body size and shape, research has suggested that genes and discrete biochemical signals contribute to the development of eating disorders. Anorexia nervosa and bulimia nervosa occur most often in adolescent females and are often accompanied by depression and other comorbid psychiatric disorders. For low-weight patients with anorexia nervosa, virtually all physiologic systems are affected, ranging from hypotension and osteopenia to life-threatening arrhythmias, often requiring emergent assessment and hospitalization for metabolic stabilization. In patients with frequent purging or laxative abuse, the presence of electrolyte abnormalities requires prompt intervention. Family-based treatment is helpful for adolescents with anorexia nervosa, whereas short-term psychotherapy, such as cognitive behavior therapy, is effective for most patients with bulimia nervosa. The use of psychotropic medications is limited for anorexia nervosa, whereas treatment studies have shown a benefit of antidepressant medications for patients with bulimia nervosa. Treatment is most effective when it includes a multidisciplinary, teambased approach.