In 1968, Steinberger left Columbia University and accepted a position as a department director at CERN. He constructed an experiment there utilizing multi-wire proportional chambers (MWPC), recently invented by Georges Charpak. The MWPCs, augmented by micro-electronic amplifiers, allowed much larger samples of events to be recorded. Several results for neutral kaons were obtained and published in the early 1970s, including the observation of the rare decay of the neutral kaon to a muon pair, the time dependence of the asymmetry for semi-leptonic decays, and a more-precise measurement of the neutral kaon mass difference. A new era in experimental technique was opened.