Abstract: The present invention relates to an arrangement for the rotary actuation of an apparatus, for example of a crane, on a chassis or a foundation wherein a worm gear (1) and a housing (2) are secured on the foundation, a worm (3) is rotationally displaceable manually, or by a drive motor, and a worm wheel (4) is rotationally mounted to the housing (2). The worm wheel (4) is provided at both sides (6a, 6b) of its gearing (6) with a separate rolling bearing (10, 11, 12). Advantageously, housing (2) is formed with a base part (2a) and a cover part (2b) which can be flatly fixed on top of the base part (2a), and at least one end side of the worm wheel comprises a connection attachment which intersperses the base and/or the cover part.