A syringe infusion pump (20) is disclosed for use with a plurality of different syringes having different barrel diameters. The pump comprises a drive head (22) including a force sensor (32) which is positioned to sense the force applied to the plunger by the drive head. A syringe barrel holder (24) is configured to hold each syringe barrel with the barrel axis automatically aligned with the centre of the force sensor (32) for each different diameter syringe barrel.
