Collaboratory musical group between Steven Wilson and Aviv Geffen. It temporarily become Geffen-led with Wilson taking a more passive role for "Blackfield IV", with his involvement as a contributor rather than a member. He resumed a full partnership with Geffen on Blackfield V. Band members are drummer Tomer Z, bassist Seffy Efrati, and keyboardist Eran Mitelman. Former band members include Chris Maitland (replaced by Tomer Z, 2004) and Daniel Salomon (replaced by Eran Mitelman, 2007).