Provided is an auto-injector for a syringe suitable for the injected delivery of drug to a patient. The auto-injector comprises a cassette unit arranged for receipt of a syringe. The cassette unit and/or syringe is movable from a rest position, in which the syringe needle tip is within the drive unit housing to a use position, in which the needle tip protrudes from a needle delivery aperture thereof. The auto-injector comprises a drive unit arranged for docking receipt of the cassette unit at a docking position and a drive arrangement. The drive unit is arranged for initial receipt of the cassette unit at an intermediate pre-docking position and for subsequent transport of the cassette unit to the docking position. In embodiments, the drive unit is arranged such that transport of the cassette unit to the docking position is permitted only following verification of an identifier at the intermediate pre-docking position.