A permanent magnet (PM) rotor has a plurality of partial laminated stacks that are interspaced in the axial direction at a defined distance, thereby defining radial cooling slots. Permanent magnets are arranged in every partial laminated stack in inner pockets. The dimension of every permanent magnet in the axial direction does not or only insignificantly exceed the axial dimensions of the respective partial laminated stack. During assembly, the permanent magnets can be axially pushed through the inner pockets to the respective partial laminated stack (20). The rotor has a very high degree of efficiency.