The frequency of short stature was assessed in 598 children (66% boys, 34% girls) referred consecutively because of asthma or allergic rhinitis. Six percent were of small stature, with heights of less than the third percentile for age. A total of 66 children with small stature were subsequently studied, 36 of whom had asthma. None had received steroids. Children with short stature were predominantly boys (83%, p less than 0.005) and had delayed bone age (less than 2 SD of mean, 34/45), correspondence of bone age with height age (r = 0.93), normal serum thyroxine but increased tri-iodothyronine levels (11/24), and normal insulin-induced growth hormone secretion (12/12). Their heights corresponded only in part to midparental height. The results were the same for those with and without asthma, and the severity of asthma was not related to the degree of growth retardation. The findings suggest that short stature is more common than expected in children with allergic respiratory disease, both asthmatic and nonasthmatic, that their growth potential is good, and that impaired linear growth is not necessarily a result only of asthma but of a more fundamental abnormality possibly associated with the atopic state. They emphasize the importance of considering allergic respiratory disease in the clinical evaluation of children with small stature.