The invention relates to bipolar plates for electrochemical fuel cell assemblies, and in particular to configurations of bipolar plates allowing for multiple fluid flow channels for the passage of anode, cathode and coolant fluids. Embodiments disclosed include a bipolar plate (10) for an electrochemical fuel cell assembly, comprising: a first plurality of fluid flow channels (13) extending across a first face of the bipolar plate between first inlet and outlet ports (18a, 18b) at opposing ends of the bipolar plate; a second plurality of fluid flow channels (22) extending across a second opposing face of the bipolar plate between second inlet and outlet ports (21a, 21b) at opposing ends of the bipolar plate; and a third plurality of fluid flow channels (14) extending between third inlet and outlet ports (19a, 19b) at opposing ends of the bipolar plate, the third plurality of fluid flow channels provided between first and second corrugated plates (11, 12) forming the first and second opposing faces of the bipolar plate, wherein the first, second and third fluid flow channels are coplanar.