a lamp changer for use with a slide projector having a projection lens and a removably modular projection lamp unit insertable through an access door opening . the lamp changer has a housing releasably connectable to the projector at the access opening and a lamp holder for holding at least two projection lamps . the lamp holder is mounted in the housing for pivotable movement about a first axis to successively position each lamp in the lamp holder in direct alignment with the projection lens . movement of the lamp holder is effected when desired and the new lamp is moved into alignment with the lens and is energized .