A pair of jaw members for an electrosurgical instrument is manufactured by providing first and second jaw members (2 & 3), each jaw member including a planar sealing surface (5 & 7). The jaw members are assembled with the first and second jaw members in a required orientation such that the planar sealing surface (5) of the first jaw member (2) is at a predetermined orientation with respect to the sealing surface (7) of the second jaw member (3). The first and second jaw members are held in the required orientation, and pivot holes (11 & 12) are formed in the first and second jaw members while they are held in the required orientation. When a pivot pin is inserted through the pivot holes in the first and second jaw members, the first and second jaw members are assembled into a pair of jaws.
