Born in 1945 in Haarlem, The Netherlands and with a background that includes playing and recording with a rock band in the late ’70s and early ’80s, her subsequent career has centered around music that draws from free improvisation and avant jazz as well as chamber classical-informed modern composition. She has also composed for film and theater. With a long history as a bandleader leading many groups showcasing improvisers as well as her own compositions, she nowadays mainly focuses on composing, and improvising with Duo Baars-Henneman, playing solo concerts and performing with ad hoc combinations.

Henneman manages the Wig label, an Amsterdam-based imprint together with her partner. Her music is heard in hundreds of concerts throughout Europe, North America, Brazil and Japan.