Poor growth is reported in as many as 50% of HIV-infected children. HIV infection adversely affects pregnancy outcome; infants born to HIV-infected women have significantly lower mean birth weight and length, regardless of the infants' HIV status, compared with infants born to uninfected women. Pediatric HIV further reduces birth weight. Progressive stunting, that is, proportionately decreased linear and ponderal growth, appears to be the most common abnormality in perinatally infected children and is accompanied by preferential decreases of fat-free or lean body mass. Although data are inconsistent, deficiencies of several micronutrients with the potential to affect growth adversely have been identified, including that of vitamin A. Neuroendocrine abnormalities also occur, including abnormal thyroid, growth hormone/ insulinlike growth factor-1, and adrenal function; however, no consistent endocrine abnormality is observed in HIV-associated growth failure. Infections of the gastrointestinal tract and malabsorption of carbohydrates, fat, and protein are common, but no relationship between these disorders and poor growth has been demonstrated. Despite normal rates of resting and total energy expenditures, the mean daily dietary intake of children with growth failure (GF) appears to be inadequate. Inadequate dietary intake is not the sole cause of GF; dietary supplementation improves weight but does not correct deficits in lean tissue or height. Levels of HIV RNA are greater in children with poor growth compared with infected children with normal rates of growth. How HIV replication impedes growth has not been established but suppression of HIV appears to have a favorable effect on ponderal and linear growth. Further investigations are necessary to evaluate the potential role of anabolic agents for the management of HIV-associated growth failure.