Radionuclide bone scanning carried out with technetium radiopharmaceutics detects almost all prostatic carcinoma osseous metastases. It is easy to recognize focal areas of increased tracer uptake or a diffuse increased uptake, and the test provides a synthetic view of the entire skeleton. Complementary bone radiographs are necessary if the diagnosis remains doubtful, if mechanical complications are searched and if there is a post-radiotherapeutic decrease of the tracer uptake. A bone scan is necessary before the radical treatment of the primary tumour, in order to rule out the possibility of bone metastases. The initial bone scan has also a pronostic value. However, in the follow-up of initially non-metastatic patients, serial bone scans should not be realized when clinical symptoms or biological abnormalities lack. Bone scintigraphy is also useful to monitor the course of bone metastases under treatment, especially when the value of new therapeutic agents is investigated.