Dr. David Mathieu is a full professor at the Université de Sherbrooke within the Departments of Surgery, Division of Neurosurgery, and Nuclear Medicine and Radiobiology, in addition to holding the post of the director of the Neurosurgery Division and of the Gamma Knife Radiosurgery Center at the Centre Hospitalier Universitaire de Sherbrooke (CHUS). He serves on the board of directors of the International Radiosurgery Research Foundation (IRRF), a research organization dedicated to the development of multicentric stereotactic radiosurgery trials. Dr Mathieu is in charge of clinical research in neuro-oncology at CHUS and has completed numerous research collaborations with members of the Neuroscience Center and the Radiotherapy Research Center of the Université de Sherbrooke. His areas of expertise include neuro-oncology and stereotactic and functional neurosurgery.