Born in Krefeld, Neuenfels studied at the Max Reinhardt Seminar in Vienna in the 1960s, and in the 1970s he quickly established himself as a leading practitioner of German Regietheater. Being invited to prominent venues, such as the Burgtheater, his productions were often controversially received, but he worked at the same time with well-known actors such as Klaus Maria Brandauer, Bernhard Minetti and. His opera productions have often been accompanied by heated discussions and scandals. In particular his version of Aida in 1980 for Frankfurt, conducted by Michael Gielen, in which he portrayed Verdi's Ethiopian slave as a cleaning woman in a contemporary setting, or his Fledermausin 2001 for the Salzburg Festival, which provoked angry reactions and resentment. Neuenfels has been criticised for creating extremely sexually explicit opera scenes. SopranoKarita Mattila criticised him in 2000 for a Salzburg production of Mozart'sCosì fan tutte in which huge insects and background videos, some of them erotic, distracted attention from the singers; during Fiordiligi's fiery aria "Come scoglio", Mattila arrived onstage walking two men, in leather and chains, as if they were dogs. She called that the worst experience and said she believed Neuenfels had crossed the line. Later, in December 2003, Neuenfels' production of Mozart's Idomeneo at the Deutsche Oper Berlin included a scene in which the title character staggers on stage carrying the severed heads of Neptune, Jesus, Buddha and Mohammed. After the police warned that the production might present a security risk, the opera house cancelled future performances, planned for September 2006. Following protests that the opera house was engaging in self-censorship, its manager,, rescheduled those performances for December 2006; see 2006 Idomeneo controversy. Neuenfels debuted in 2010 at the Bayreuth Festival with Wagner's Lohengrin, conducted by Andris Nelsons. This production set the opera in a laboratory and featured chorus members costumed as lab rats. The audience reaction at the premiere ranged from enthusiastic applause to irate booing. According to Der Spiegel, Neuenfels merely smiled and shrugged after taking his curtain calls.