ROLAND DAHINDEN and HILDEGARD KLEEB have been working together since 1987 in Europe and America and in collaboration with visual artists Daniel Buren, Stephane Brunner, Rudolf de Crignis, Philippe Deleglise, Sol LeWitt and architects Morger and Degelo. Many composers, including Peter Ablinger, Maria de Alvear, Anthony Braxton, John Cage, Peter Hansen, Hauke Harder, Chris Newman, Pauline Oliveros, Lars Sandberg, Heinz Weber, Daniel Wolf and Christian Wolff, have written works especially for them. Dahinden and Kleeb are also improvisers and have developed a form of collective composition.