Stephen Mangar is a Consultant Clinical Oncologist and Honourary Senior Lecturer at Imperial College Healthcare NHS Trust, Hammersmith site. He is also the Lead for uro-oncology North West London Hospitals NHS Trust. He has trained in all aspects of clinical oncology, including radiotherapy, chemotherapy, and treatment with targeted therapies. He specialises in the delivery of highly conformal image-guided radiotherapy using techniques, such as Intensity-Modulated radiotherapy (IMRT), Cyberknife for pelvic tumors, and stereotactic ablative radiotherapy (SABR) for metastatic disease. His research interests in chemotherapy are to develop treatments for prostate, bladder, and colorectal cancers and explore new chemoradiotherapy regimes for lung cancer. He has a significant research portfolio, being principal investigator for a number of national trials as well as various commercial trials. He is also the Chief investigator for various studies investigating novel PET tracers for prostate cancer and for developing imaging biomarkers. He is a member of the European Society for Radiotherapy and Oncology (ESTRO), the American Association for Cancer Research (AACR), the British Uro-oncology Group (BUG), the Royal College of Physicians, and the Royal College of Radiologists (RCR).