Book Review: Darren Langdridge and Meg Barker (Eds.) Safe, Sane and Consenusal. Contemporary Perspectives on Sadomasochism. Houndmills, Basingtoke, Palgrave Macmillan, 2007. 310pp. ISBN-13: 978-0-23-51774-5 (Hbk) ISBN-10: 0-230-51774-9 (Hbk)