Distributed electron cyclotron resonance or DECR, a new plasma excitation technique well adapted to microwave multipolar plasmas, is described. The novel reactor concept is based upon the use of several microwave linear applicators working at the ECR mode along the multipolar confinement magnets. At a microwave frequency of 2.45 GHz, large volumes of highly homogeneous plasmas with an electron temperature of the order of 3 eV and ion densities better than 1011 cm−3 are currently being produced in DECR reactors.