Mauricio Kagel (born Buenos Aires, December 24 1931) is an Argentine composer who has lived in Cologne, Germany since 1957. He is most famous for his interest in developing the theatrical side of musical performance. Many of his pieces give specific theatrical instructions to the performers, such as to adopt certain facial expressions while playing, to make their stage entrances in a particular way, to physically interact with other performers and so on. Wikipedia
The definitive Wikipedia entry for Mauricio Kagel. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Mauricio_Kagel
Mauricio Kagel talks about his early years in Europe, his youth in Argentinia, his roots in the East-European Jewish culture and his view on 'absolute music'. A conversation with Max Nyffeler www.beckmesser.de/neue_musik/kagel/int-e.html