The invention relates to a guide system for optical systems, particularly for zoom systems, with which optical assemblies such as lenses and/or sets of lenses can be moved along an optical axis (16). The proposed guide system comprises a housing (2) defining an internal diameter (1) and extending along the optical axis (16). A slide (3) is configured to accommodate an optical assembly (19) and has a sleeve segment (15) which has on its outside a plurality of contact surfaces (4) for abutment on the internal diameter (1) of the housing (2). For defined movement of the slide (3) along the optical axis (16) a drive unit (12) is provided. A device (17) serves to hold the sleeve segment (15) at the internal diameter (1), another device (18) serves to secure the slide (3) against rotation in the cross-sectional area of the housing. The guide system according to the invention provides guidance which is absolutely free from play and low in friction. Openings (10) in the housing allow access to the lenses for adjustment and cleaning.