Karlheinz Stockhausen's In Freundschaft (In Friendship) is an occasional work composed in July 1977 as a birthday gift for the clarinetist Suzanne Stephens. Stockhausen indicates that any of several "melody" instruments—including flute, oboe, basset horn, and trombone—may be used in performances of the work. In Freundschaft, about 14 minutes in duration, is a clear example of Stockhausen's "formula" method of composition. The opening melody supplies the material on which the entire piece is based; its most important element is a mid-range minor second trill, which forms a kind of axis (not unlike like the drone on B in Luciano Berio's 1969 Sequenza VII for oboe). The "formula" is followed by three Cycles (akin to variations on a theme), then a cadenza ("Explosion I"), three more Cycles and another Explosion, and a seventh Cycle. A concluding section mirrors the opening.

In Freundschaft was first performed by flautists Lucille Goeres and Marjorie Shansky at a private birthday party for Suzanne Stephens. The piece was first performed publicly by Goeres at the Conservatoire Darius Milhaud in Aix-en-Provence. In the year following its completion, Stockhausen expanded the work; this version was premiered by clarinetist Stephens in Paris in November 1978.

© Robert Kirzinger, All Music Guide