OBJECTIVE High-dose steroid therapy in children is known to impair growth. What is unknown is the level of steroid therapy at which children continue to grow normally. This study was designed to deduce a dosage of prednisolone compatible with normal growth. METHODS The growth of 41 children (age 1.92-13.2 years) with steroid-dependent nephrotic syndrome (SDNS) was studied using recordings from clinic visits over the course of their follow-up at Great Ormond Street Hospital (study period range 1.38-8.43 years, mean 4.2 years, total 172 years). The height standard deviation score (SDS) and the SDS velocity between clinics were calculated, and compared to the contemporary dose of prednisolone (converted to an equivalent daily dose when on an alternate day regime). RESULTS The mean dose of prednisolone was 0.44 mg/ kg/day (range 0.06-1.45 mg/kg/day). The mean change in height SDS velocity over the course of recording was -0.02 SDS/year (boys -0.14 SDS/year, girls +0.16 SDS/year). Overall, there was no negative effect on growth seen at doses of prednisolone of less than 0.75 mg/kg/day. At doses higher than 0.75 mg/kg/day, there was a small decline in height SDS velocity (-0.14 SDS/ year). CONCLUSIONS Overall, prednisolone treatment in these children was not shown to adversely affect their height SDS. This was true even at doses of prednisolone up to 0.5-0.75 mg/kg/day. There was some decline in height SDS seen during periods of higher steroid use (over 0.75 mg/kg/day), but periods on lower doses allowed for adequate catch up growth.