My interest in children with growth problems was stimulated by hearing the 1964 Windermere Lecture given to the British Paediatric Association (Prader et al). Since these early exciting studies of growth hormone treatment there has been debate about the best way of identifying patients who might benefit from it. When the only preparations available were derived from human pituitaries, and supply was limited, the opinion was readily accepted that only patients with very low serum levels after pharmacological stress should be treated. The demonstration of a serum growth hormone of more than 15 mU/1 after any stress was accepted as an indication that treatment was not indicated.