'In my own marriage I paid such a terrible price for sex-ignorance that I feel that knowledge gained at such a cost should be placed at the service of humanity.' The book that was to become Married Love grew from Marie Stopes's conviction that the state of modern middle-class marriage was, like her own, desperate, and that the cause of this desperation was sexual unhappiness. She knew her book would 'probably electrify this country' and it remains one of the best known sex manuals ever written. It combines a lyrical evocation of marital love with a no-nonsense and detailed account of sexual intercourse and sexual pleasure that was a sensation when it was published in 1918. Stopes advocated equality in marriage and the importance of women's sexuality and sexual desire, as well as openly supporting birth control. In this edition of Stopes's ground-breaking work, Ross McKibbin's introduction reveals fascinating insights into Stopes and prevailing attitudes to class, religion, science, and above all, sex.