Abstract: A bonding head (10) of a wire bonding machine for bonding wire to electronic or electronical components comprises a bonding tool (18) connected to an ultrasonic transducer (16), a wire spool (22) mounted at the opposite side of the head to the transducer (16), and (optionally) a guide (60) including a tubular member (62) adjustably mounted on the head (10) having an inlet end through which wire (20) from the spool (22) passes and an outlet end (64) adjacent the bonding tip (19), the guide (60) being mounted for angular movement on an arm (70) itself pivotally mounted whereby the angle of the guide (60) can be adjusted while maintaining the outlet end (64) in position adjacent the bonding tip (19). Thus the wire (20) can be supplied to the tool (18) at a variety of different angles according to the component to which the wire is to be bonded.