Malignant brain tumours have a dismal prognosis with current state of the art technology. The main reasons for this lost battle in the battlefield of cancer are tumour cell invisibility to the surgical microscope and brain invasion. However, the vast majority of these tumours relapse locally making local radical removal the main strategy in their successful eradication. PDD and PDT combined with new technology stands a very good chance of achieving this goal by maximising tumour resection (POD) and selective tumour kill (PDT). The aim of this paper is to explain how this is done at Ninewells Hospital and Medical School, Dundee, Scotland. The technique and technology described in this paper, provide a means of diffusing the light to the periphery of the tumour cavity with subsequent therapeutic sessions and treatment dose escalation at the bedside, saving time and resources. (C) 2004 Elsevier B.V. All rights reserved.