A hybrid magnet for an MRI machine, the magnet comprises a superconducting coil and a pole piece assembly associated with therewith. The pole piece assembly comprises a ferromagnetic member having a primary face for facing a subject to be imaged. A shim unit is separated from the primary face of the ferromagnetic member. A plurality of field-shaping permanent magnets is situated between the shim unit and the primary face of the ferromagnetic member.