Emphasizing that accurate diagnosis is the foundation for effective treatment regimens, this reference reviews the most current research on the assessment, epidemiology, etiology, risk factors, neurodevelopment, course of illness, and various empirically-based evaluation and treatment approaches relating to eating disorders-studying disordered eating in atypical patient populations, such as men, infants, and the elderly and highlighting gender, cultural, and age-related differences that have appeared in the study of these conditions.