His first collection, The Imageless World (Salt Publishing, 2003) was short-listed for the Victorian Premier’s Award for Poetry and won the Mary Gilmore Award. In 2006, he undertook residencies in Berlin and Paris thanks to the Marten Bequest Travelling Scholarships, the Literature Board of the Australian Council for the Arts, and the Cité Internationale des Arts, Paris. That same year, Brennan published a chapbook titled Language Habits, followed in 2007 by a chapbook collaboration with Japanese artist Akiko Muto, translated by Yasuhiro Yotsumoto. An artbook collaboration with Sydney artist Kay Orchison titled Atopia and a second collection from Salt Publishing titled Unanimous Night are forthcoming.