The availability of highly active antiretroviral therapy (HAART) has resulted in dramatic declines in morbidity and mortality in patients infected with human immunodeficiency virus-1 (HIV-1). However, the success of HAART has been tempered by the recognition of adverse metabolic effects clearly associated with its use. These "metabolic complications" include dyslipidemia, changes in body fat distribution, insulin resistance and glucose intolerance, metabolic bone disease, and lactic acidosis. Guidelines to assist clinicians in the management of these complications have been put forth by various organizations, including the International AIDS Society, the HIV Medicine Association of the Infectious Disease Society of America, and the Adult AIDS Clinical Trials Group.