To compensate for tolerances and diameter differences during the chucking of a tool shank (15) in a tool holder (1) of the shrink-fit chuck type, a diameter-compensating bush (17) is provided. The diameter-compensating bush (17) has an outer sleeve (19) having a tapered inner circumferential surface (25) and an inner sleeve (21) arranged coaxially therein and having a tapered outer circumferential surface (27). Once the diameter-compensating bush (17) has been put onto the tool shank (15) and the inner sleeve (21) has been drawn into the outer sleeve (19), for example by means of a ring nut (35), for the diameter compensation, the outer sleeve (19) is thermally shrunk in place in the locating section (9) of the tool holder (1). In this way, rotary tools whose tool shank (15) does not have a diameter corresponding to the diameter or the tolerance requirements of the tool holder (1) can be chucked in a tool holder (1), for example, of the shrink-fit chuck type.