Epitaxial CdSe layers were electrodeposited from a standard aqueous electrolyte onto a (111) InP single crystal. By using various characterization techniques (RHEED, XRD, HREM,...) it was demonstrated that a good epitaxy can be achieved by monitoring the experimental parameters very carefully, in particular the selenium concentration in the electrolyte and the deposition potential. For optimum conditions, the composition of the semiconducting layer is close to stoichiometry and the carrier density is around 1 × 1017 cm−3.