In the first part of this article we discuss some special technical aspects of percutaneous bone biopsy (PBB). But our main intention is to illuminate the critical indication of PBB against the background of the diagnostic and clinical utility. Reliable indications for PBB are: lytic metastases, solitary lytic lesions in a patient with known primary tumour and infection. Sclerotic metastases and vertebral compressions, on the other hand, have a lower diagnostic utility. Negative biopsies must be interpreted carefully and repeated if considered to be nonrepresentative The indication for percutaneous biopsy of primary bone tumours remains doubtful. Most of them require open biopsy.