Abstract: An aid for helping a golfer to improve his swing in which an arm-mountable harness (11, 12) links the handle of a golf club (13), in use, to the elbow of the golfer's secondary club driving arm in a manner which enables the golfer to grip the club-handle (13) with his primary driving arm and, having then temporarily stabilised the position of his secondary arm with respect to his upper body, impact the club head against a waiting ball in an otherwise conventional one-handed swing during which the elbow-to-club link of the harness replaces the forearm of his secondary arm.