Bentley studied under W. H. Auden. He was a friend and colleague of Theodore Roethke, among other Northwest poets who created a distinct regional voice. In his forty years as a professor he conducted workshops, hosted readings at literary venues around the city and on radio and public television, juried poetry contests, edited poetry for journals and newspapers, and was a co-founder of Poetry Northwest and The Seattle Review. Although he was a fine poet in his own right, he believed his own greatest accomplishment to be his work in teaching hundreds of other poets who published in nationally recognized poetry outlets. He founded the Castalia Reading Series, which started at the University of Washington in the mid-seventies and continues today.