The installation of the novel post-accelerator REX-ISOLDE has opened up new fields of research with radioactive ion beams of higher energies, in particular light-medium mass nuclei for reaction studies with energies up to 3.1 MeV/u. As part of an agreement between CERN and the ISOLDE collaboration CERN has taken over the running of REX as part of the host facility and four full-time posts have been created to provide this function. REX is operational and has already accelerated several species of radioactive ions, e.g. 10,000 ions/s of 29Na; it has the capability to accelerate mass 140 ions and heavier with efficiency of a few percent of the ion source yield. REX will be upgraded in 2013-2014 to provide a maximum energy of 5.5 MeV/u, reaching the Coulomb barrier threshold for a wide range of nuclei.