A stator for an electrical machine (e.g., a motor or generator) is described. The stator includes a stator core consisting of a plurality of axially adjacent generally annular laminations. The stator has axially extending stator teeth between adjacent pairs of which are formed axially extending stator slots for receiving conductors of a stator winding. At least one of the stator teeth includes an axially extending cooling passageway through which a cooling fluid flows in use. The electrical machine can include means for circulating cooling fluid through the cooling passageway(s) to cool the stacked laminations and means for circulating air around the stator along an air cooling circuit where the circulated air is cooled by the stator laminations and there is no need for a separate heat exchanger.