Trailer coupling with a sensor

The trailer coupling (10) comprises a support (13) which is attachable to the chassis of motor vehicle (12). The housing (15) of the traction coupling (16) of trailer is placed in a coupler pocket (18) such that the housing is rotatably supported relative to the support. A sensor assembly (30) is provided for detecting the angular position of traction coupling relative to the support. A drive unit (33) is inwardly arranged in the support for driving the coupler pocket with respect to the outer surface (23a) of the spherical surface (23) of coupling housing.