The locking arrangement consists of key a and lock cylinder with a guide cross section provided on the rear of the key shank and with profiled longitudinal ribs arranged on the broad face for entry into associated grooves of the lock cylinder key channel. Transversely to the profiled longitudinal ribs, there are provided wards which issue from one narrow edge of the key shank and, in their depth, follow the unit or multiple of the step jump (x) of the lock cylinder core pins. At least the lower rib flank facing the narrow edge of the key shank is perpendicular to the longitudinal center plane of the key shank and the distance of the lower rib flanks from one another is equal. The lower rib flanks are arranged at a distance from one another corresponding to the unit or integral multiple of the step jump (x) and in such a way that the deepest points of the wards are at the level of the lower rib flanks which externally pass tangentially into convexly shaped curved end faces which run tangentially into the upper rib flanks.