Bradwell, a director, playwright and actor who founded Hull Truck Theatre Company was artistic director of the Bush Theatre for over a decade before leaving the post in 2007, was presented the prize by actress Claire Bloom.
This year's judging panel was made up of Theatre Royal Stratford East artistic director Kelly Michael; last year's winner, dance writer and critic Jann Parry; and Professor Michael Dobson of London University’s Birkbeck College.
With a foreword written by director and filmmaker Mike Leigh, The Reluctant Escapologist is Bradwell's account of his travels through 1960s and 70s London fringe theatre which he describes as a "sub-culture peopled by lunatics, hippies and the perennially unemployed".
The book includes episodes such as creating a character for Leigh; witnessing the on-stage mass orgasms of the Living Theatre; teaching Bob Hoskins how to eat fire; doing battle with health-and-safety inspectors in his ten years running the Bush Theatre; and (reluctantly) becoming an escapologist in the Ken Campbell Road Show.
In his acceptance speech Bradwell said: "Thank you very much, this is for the Tigers, and thank you very much everybody here. In my book I come to a point where I think, I don't think theatre is safe in the hands of grown ups, so I hope you all never grow up."
The Society for Theatre Research’s Theatre Book Prize is presented annually for a book on British or British-related theatre that an independent panel of judges considers to be the best published during the year.