Whole-body scintigraphy with 131I-meta-iodo-benzylguanidine 131I-MIBG) was performed in 41 patients with neuroblastoma. In patients with clinical remission no pathological concentration of 131I-MIBG was found. In 30 patients with residual, recurrent or metastatic disease neuroblastoma was correctly localized by 131I-MIBG scintigraphy. It is concluded that 131I-MIBG whole-body scintigraphy is useful in the diagnosis and follow-up of neuroblastoma.