After the introduction of HAART (Highly Active Anti-Retroviral Therapy) in patients infected with HIV, a new syndrome--Lipodystrophy syndrome--has been described, in 1998. Lipodystrophy syndrome in patients with HIV infection comprises several conditions: lipoatrophy, lipohypertrophy, mixed syndrome (lipoatrophy and lipohypertrophy), often associated with dyslipidemia and insulin resistance. Lipoatrophy and lipohypertrophy can occur independently, being associated with different constellations of host, disease and drug risk factors. Until a working clinical definition on HIV-related lipodystrophy syndrome is developed, it will be difficult to monitor patients and compare studies, because, at present, investigators, clinicians and patients have different working definitions.