First results of an attempt to integrate an electro-membrane enzyme reactor with a fuel-cell stack in order to construct a multi-functional unit are presented. The experimental fuel-cell stack consists of nine single polymer electrolyte membrane fuel cells (with active cross-sectional area of 26cm(2)) consuming pure humidified hydrogen as the fuel. The stack is designed to deliver steady electric power of 30W (stack voltage of about 6V at current of about 5A). The electro-membrane enzyme reactor is composed of five flat-shaped compartments: the cathode and the anode compartments, two reactant stream compartments and the gel slab compartment. The active area of all the compartments is 9cm(2). The operating curves (current-voltage and power-current curves) of both sub-units and their dynamical behaviours have been measured over a wide range of operating conditions. A comparison of the operating curves of the fuel-cell stack and of the electro-membrane reactor confirmed that these subunits are electrically compatible and can be mutually integrated within a multi-functional unit, whilst the fuel-cell stack provides enough electrical energy to power also the necessary auxiliary equipment (pumps, blowers, etc.). (c) 2006 Elsevier B.V. All rights reserved.