An electrosurgical instrument (1) is disclosed including a housing (2) comprising an elongate main body (3), extending in an axial direction and a grippable member (12). An implement (4) is fixed relative to and projecting from a forward region of the main body (3). A smoke evacuation passage (8) is defined within the main body (3) and extends from an inlet proximal to the implement (4). An electrical conductor (11) is housed within the housing (2) for supplying an electro-surgical current to the implement (4). The grippable member (12) is slidably connected to the main body (3) such that the axial position of the grippable member (12) relative to the main body (3) may be adjusted in use. Further there is provided a controllable smoke passage obstructor (25) for enabling adjustment of the throughput of the smoke passing through the interior of the housing (2).
