Short stature and puberty delay can cause problems, both physical and psychological. Until relatively recently growth hormone was only available for children who met the criteria of "classical" growth hormone deficiency. Recombinant human growth hormone (rhGH) is now available in "unlimited" supply. Detailed studies are required to evaluate its use in short children who are not growth hormone insufficient in the traditional sense, but who may benefit from treatment. This thesis presents three studies in short normal children to evaluate the physical and psychological effects of growth promoting agents over the first two years of treatment. 1) a double blind placebo controlled study of rhGH in 37 pre-pubertal children (mean age 8.0 yrs) with familial short stature. This unequivocally demonstrates the short-term growth promoting effects of rhGH - over the first year the children treated with rhGH grew at a mean rate of 7.67 cm/yr, compared to 4.76 cm/yr for those who received placebo and 4.83 cm/yr for those who received no treatment. The onset and rate of puberty, especially in the girls, tended to be advanced. 2) in a randomised study in 43 peri-pubertal boys (mean age 11.6 yrs) with familial short stature, the growth promoting effects of rhGH were compared with the anabolic steroid oxandrolone, a combination of rhGH with oxandrolone, and a control group who received no active treatment. In the short term growth improved in the three actively treated groups compared to the control group - over the first study year the boys who received rhGH grew at a rate of 7.58 cm/yr, compared to 8.08 cm/yr for oxandrolone alone, 9.92 cm/yr in those who received rhGH plus oxandrolone, and 4.73cm/yr in the control group. In the groups who received oxandrolone, either singly or in combination with rhGH, onset of puberty was earlier and skeletal maturation more rapid. Caution is required in using oxandrolone to promote growth in younger boys without significant growth delay. 3) in a randomised study in 33 boys with puberty delay (mean age 14.9 yrs) the growth promoting effects of rhGH were compared with oral testosterone undecanoate, and a combination of the two drugs. There were no significant differences in the growth promoting effects (rhGH 8.59, testosterone undecanoate 8.48, combination 9.91 cm/yr) or rate of pubertal progression between the three groups There is no advantage Df rhGH therapy in boys with puberty delay, compared to oral testosterone undecanoate. Children of short stature are often thought to suffer from psychological or behavioural problems. A range of self report questionnaires was undertaken in these children prior to entry into the studies and at yearly intervals. They were not as a group clinically disturbed, but tended to score highly on hyperactivity. In those who received active treatements, especially rhGH, the reported behaviour and self esteem tended to improve, but the effects were not marked. It is possible to accelerate the growth of short normal children, at least in the short term, though it is less likely there will be a significant improvement in final height. There are psychological effects of growth promotion but they are subtle. It is difficult to justify the use of rhGH in young children with familial short stature, or in boys with puberty delay. Growth hormone must not be used indiscriminately in the short normal child.