There is disclosed a laparoscopy trocar, having a cannula and an obturator for use in inserting the cannula into the abdominal cavity of a patient. The cannula comprises a fluid control valve for opening and closing a fluid flow path from outside the bore of the cannula into the bore of the cannula and the obturator comprises a control means configured to cause the fluid control valve to move between its open and closed positions upon insertion of the obturator into the cannula. A novel tip for the obturator is disclosed comprising a concave bladed front edge formed between a pair of concave tip faces.