AbstractMuon catalyzed fusion or “cold fusion” has become a research topic of great new interest. Due to a resonance mechanism in dμt mesic molecule formation, fusion yields exceeding 100 per muon were observed in experiments at LAMPF and PSI. μα sticking after dt fusion seems presently to be the main limitation of fusion output.An introduction to this field is given and recent development in theory and experiments presented. The kinetics of the dμt cycle is rather complex and poses several open questions with respect to muon transfer, mesic molecule formation and sticking. Recent measurements show the temperature and density dependence of fusion rates. The results for sticking are somewhat controversional and indicate lower values than theoretically expected. Reactivation of the μα system may be the crucial process to reduce sticking. Several schemes of possible future exploitation are discussed.