The variety of endocrine late-effects after brain tumour therapy in childhood is well known. Growth is usually impaired first due to a hypothalamo-pituitary growth hormone (GH) deficiency or a radiation-induced neurosecretory dysfunction of GH secretion. Generally, all hypothalamo-pituitary axes can be affected. Disturbances of puberty, gonadal function, thyroid function and adrenal function can manifest after a long posttherapeutic interval. A retrospective analysis of the auxological and endocrinological data assessed within the German brain tumour study HIT 91 showed that endocrinological follow-up of these patients was not satisfactory. Therefore we have developed a concept for the new brain tumour study: auxological and laboratory parameters will be assessed before oncological therapy and in regular intervals (4, 12, 18, 24 months after the end of tumour therapy). 24 months after the end of tumour therapy all hypothalamo-pituitary axes are to be evaluated with pharmacological stimulation tests.