Blood pumps discussed herein may be suitable for use as a ventricular assist device (VAD) or the like. The blood pumps cause minimal blood damage, are energy efficient, and can be powered by implanted batteries for extended periods of time. Further, these pumps are also beneficial because they may improve the quality of life of a patient with a VAD by reducing restrictions on the patient's lifestyle. The blood pumps can provide radial and axial stability to a rotating impeller that is driven by a separate rotor. Both radial and axial stability can be provided, at least in part, by one or more permanent magnetic couplings between the rotor and the impeller and/or one or more permanent magnetic bearings between the pump housing and the impeller.