Stature and its components were examined in 143 girls aged 11 to 15 years with adolescent idiopathic scoliosis. Correction was made for loss of height due to the lateral spinal curvature, and the findings were compared with those from 202 healthy girls of similar age. Using three components of stature (suprapelvic, pelvic and subischial heights) we were able to show that the relatively greater stature of girls with adolescent idiopathic scoliosis was due to changes in the pelvis and lower limbs but not significantly in the spine. Suprapelvic height was reduced relative to subischial height; this probably represents the growth pattern of predominantly ectomorphic individuals, reflecting the physique of many of these girls. Pelvic height was disproportionately increased, and this is considered to be a true rather than an apparent difference. Cephalocaudal disproportion involving two segments suggests a common mechanism of causation which is unlikely to be secondary to the scoliosis. These physical features may in some way be associated with a predisposition to progression of the scoliosis.