"The astrophysical enigma of dark matter, that most of the matter in the Universe appears only gravitationally, persists since 1933. The Astroparticle Physics European Coordination (ApPEC) recognizes that this is a question of fundamental importance. Particle physics propose weakly interacting massive particles (WIMPs) that could solve this problem. Detecting WIMPs is a tremendous challenge. The most sensitive experiments, such as EDELWEISS in Europe, and CDMS in North-America, use cryogenic ionization-phonon detectors that are very efficient at rejecting radioactive backgrounds. These experiments currently deploy about 10 kg of detectors. Improving their sensitivity will require scaling up to masses of a ton. This will only be feasible in a larger, transatlantic collaboration; the ApPEC roadmap emphasizes the necessity of such large-scale collaborations. This International Cryogenic Experiment (ICE) proposal lays the groundwork for such an endeavour. The candidate, a key member of EDELWEISS, will spend time in the CDMS collaboration at UC Berkeley and its Stanford partner. Issues that will be studied include exhanges of data and detectors between the experiments, scaling up detector modules from hundred gram scale to five kg scale, and improving the background rejection of surface events using the luminescence of germanium. The outgoing host is ranked among the top universities in the world, instigated the field of dark matter searches, and boasts an outstanding record in training. The return host, Institut de Physique Nucléaire de Lyon, of Université Lyon 1, has strong experience dealing with international collaborations, and is an important European players in dark matter experiments. Project ICE will give the candidate enough experience and international exposure to apply for a senior-level position upon his return. Europe will benefit from the training he will receive, and from gaining a foothold in the future ton-scale experiment."