Short stature is one of the commonest chronic problems encountered in pediatric practice. We studied 477 GH deficient patients on rhGH therapy for a duration of 1 to 7 years. Patients received GH at a fixed dose of 20 IU/m²/day. Statistical analysis for the patients’ auxological data basally and in the subsequent years of therapy, was performed. Multiple linear regression analysis was performed on idiopathic prepubertal patients to find correlators of growth for the first 4 years of therapy. Height SDS improved from -4.4 to -2.9. In the first year of therapy, the most important predictor was peak GH level (ug/l). Our conclusions were that prediction models are crucial for individualizing therapy and that GH therapy is generally safe.