Congenital Generalized Lipodystrophy (CGL) or Berardinelli-Seip Syndrome (BSCL) is a rare autosomal recessive disease characterized by complete absence of adipose tissue and by several metabolic alterations in carbohydrate (diabetes mellitus) and lipid metabolism and involvement of heart, bone and ovaries. Mental retardation and psychiatric disturbances are present in a variable proportion of affected patients. In the present review, the major advances in clinical, molecular and genetic characterization of BSCL affected subjects are recorded and discussed.