SEMINAR      Thursday, 27 January 2005 - h. 15:00  Auditorium B. Touschek     H. Satz (U. Bielefeld, Germany and Instituto Superior Tecnico, Lisbon, Portugal ) Deconfinement in QCD and in Nuclear Collisions Abstract     I first survey critical behaviour in strongly interacting matter and summarize the results obtained in finite temperature lattice QCD.       Subsequently, I address the efforts to produce the predicted quark-gluon plasma in high energy nuclear collisions and consider possible probes to investigate the resulting medium.