The present retrospective study includes all children suspected for having neuroblastoma, admitted to Odense University Hospital in September 1984 through December 1993. Thirty-six children at the age range of 1 month to 14 years and 10 month were investigated with 123I-metaiodobenzylguanidine (MIBG). Nineteen children had histologically verified neuroblastoma. Several MIBG scintigraphic examinations were made in all but one of these 19 children. Positive MIBG scintigraphy strengthened the diagnosis and indicated the volume and location of the tumour at diagnosis and during the treatment period. In a few patients only there was some disagreement between results obtained with MIBG scintigraphy and standard investigations as CT-scanning or ultrasonography. MIBG scintigraphy in all cases turned out to be the most sensitive modality.