A fuel cell assembly has a plurality of fuel cell component elements extending between a pair of end plates to form a stack, and plural reactant gas manifolds mounted externally of and surrounding the stack, in mutual, close sealing relationship to prevent leakage of reactant gas in the manifolds to the environment external to the manifolds. The reactant gas manifolds are configured and positioned to maximize sealing contact with smooth surfaces of the stack and the manifolds. One embodiment is configured for an oxidant reactant manifold to overlie the region where the fuel reactant manifold engages the stack. Another embodiment further subdivides an oxidant reactant manifold to include a liquid flow channel, which liquid flow channel overlies the region where the fuel reactant manifold engages the stack.