The electrochemical behaviour of platinum electrodes in aqueous solutions containing carboxymethylcellulose, CMC and pyrrole was followed by voltammetry and chronopotentiometry. The electrogeneration of a composite polypyrrole-CMC at potentials above 500 mV vs SCE is influenced by the relative concentrations of pyrrole and polyelectrolyte. Electrolyte adsorption prevails on the electrode at concentrations of pyrrole below 0.1 M. The monomer oxidation is diffusion controlled. The polymerization process was followed by "ex situ" gravimetric determinations at different temperatures ranging between 5 and 50 degrees C. Productivity of the consumed charges and charge storage efficiencies in the electrogenerated films were obtained. Selected electrodeposition variables are typically : [Pyrrole], [CMC], T degrees C, E vs SCE.