A significant proportion of elderly emergency department visits are for acute infections. The elderly are more likely than younger patients to have nonspecific signs and symptoms of infection, more severe disease, and resistant microorganisms. As a result, emergency physicians must maintain a high index of suspicion for infection, even in the face of nonspecific symptoms, and should tailor empiric antibiotic therapies to the expected pathogens in this population. Appropriate emergency department evaluation and treatment of infections in the elderly requires consideration of these unique aspects of the geriatric patient population.