He was also co-editor with Cuscaden of Odyssey: Explorations in Contemporary Poetry and the Arts (1958–59), which published the early work of Charles Bukowski, LeRoi Jones (Amiri Baraka), David Ray, and others.
In 1975 Offen and his second wife, Rosine (1930–2000), an Actors’ Equity actress and director, formed the theater company, The Peripatetic Task Force.
The company's production of Jack Stokes's Wiley and The Hairy Man at Gangway Playhouse won a special Joseph Jefferson Award in 1977 for children's theater.
In 1989 he founded Free Lunch, which published such renowned poets as Billy Collins, Stephen Dunn, Stuart Dybek, Donald Hall, X.J.
In March 2013 Hearths (Ramparts, Inc., New Orleans, Los Angeles, and Pass Christian, MS) featured a September 10, 2009 interview conducted by editor Lenny Emmanuel of Offen, pp. 27–46.