[en] A new steady state neutron source is in operation on the Atomic Energy Commission Site of Saclay (France). It is a pool type nuclear reactor, using enriched uranium fuel elements together with a heavy water tank as moderator, and specially designed to provide neutron beams for fundamental and applied research. At full power of 14 Mw, the maximum unperturbed neutron flux reaches 3x10¹⁴n/cm²s and the reactor is operated twenty four hours per day in a three months cycle. Twenty horizontal neutron beams can be used in the reactor hall or transmitted to a large external hall by cold neutron guides. Several vertical tubes allow radioisotope production and activation analysis. In a first stage nineteen experimental facilities are planed including thirteen spectrometers for elastic scattering studies and six spectrometers for spectrometry studies