Six thousand active participants were assembled in Berlin during the XIth World Congress of Gynecology and Obstetrics. Their contribu­ tions covered the entire field of our discipline: matemo-fetal medicine, gynecologic oncology and surgery, reproductive medicine, and endocri­ nology. Emphasis was laid on the diseases of the female breast and these papers appear in a separate section of the book (B VII -X). The scientific program included 370 invited speakers for special lec­ tures, various main theme sessions, around 100 seminars, and 45 film and video presentations. A total of 1566 free communications had al­ ready been published in abstract form before the Congress convened (Archives of Gynecology, Vol. 237, pp. 1-405, 1985). The present volume contains 291 papers, representing special lectures, all main theme ses­ sions, and seminars, from the contributions of speakers invited by the Scientific Program Committee and the key-chairmen of the XIth World Congress. Unfortunately, 78 speakers did not send their manuscripts by the deadline despite two extensions, so that we had to be content with around 80% of the contributions presented during the Congress.