A guide system for guiding a movably supported furniture part, in the form of a folding door or a folding-sliding door formed by a first door wing and a second door wing, wherein the door wings (3a, 3b) are hingedly connected to one another by at least one middle hinge, comprising: - a longitudinal guide rail, - at least one guiding device configured to be arranged on the first door wing and for moving the furniture part in a longitudinal direction along the longitudinal guide rail, - at least one carrier for hingedly supporting the furniture part via the second door wing, wherein the at least one carrier is movable in a direction extending transversely to the longitudinal direction of the longitudinal guide rail, wherein the at least one carrier includes a receiving device for receiving the guiding device, and the carrier, in the mounted position, is configured to be moved into a transfer position in which the receiving device is arranged adjacent to the longitudinal guide rail, - a compensation device for compensating for a height difference between the receiving device and the longitudinal guide rail, characterized in that - the compensation device is arranged in a region between the longitudinal guide rail and the carrier and/or the receiving device, and the guiding device is configured to be transferred to and from between the longitudinal guide rail and the receiving device via the compensation device, - the compensation device is formed by a running surface arranged at an incline relative to a profile portion extending along the longitudinal guide rail, - the guiding device includes at least one running wheel, wherein the at least one running wheel is configured to be transferred to and from between the longitudinal guide rail and the receiving device via the compensation device, and - the receiving device includes a running surface and that the at least one guiding device, upon positioning in the receiving device, contacts the running surface or has a distance to the running surface. - a longitudinal guide rail, - at least one guiding device configured to be arranged on the first door wing and for moving the furniture part in a longitudinal direction along the longitudinal guide rail, - at least one carrier for hingedly supporting the furniture part via the second door wing, wherein the at least one carrier is movable in a direction extending transversely to the longitudinal direction of the longitudinal guide rail, wherein the at least one carrier includes a receiving device for receiving the guiding device, and the carrier, in the mounted position, is configured to be moved into a transfer position in which the receiving device is arranged adjacent to the longitudinal guide rail, - a compensation device for compensating for a height difference between the receiving device and the longitudinal guide rail, characterized in that - the compensation device is arranged in a region between the longitudinal guide rail and the carrier and/or the receiving device, and the guiding device is configured to be transferred to and from between the longitudinal guide rail and the receiving device via the compensation device, - the compensation device is formed by a running surface arranged at an incline relative to a profile portion extending along the longitudinal guide rail, - the guiding device includes at least one running wheel, wherein the at least one running wheel is configured to be transferred to and from between the longitudinal guide rail and the receiving device via the compensation device, and - the receiving device includes a running surface and that the at least one guiding device, upon positioning in the receiving device, contacts the running surface or has a distance to the running surface.