Endometriosis can be considered as a chronic disease which is characterized by the presence of ectopic endometrium outside the endometrial cavity and which is associated with symptoms as pelvic pain and infertility. Medical treatment is often not sufficient in patients with moderate to severe endometriosis and deep infiltrative endometriosis (DIE), therefore requiring surgical intervention. Over the past 15 years, we have built a multidisciplinary surgical team to perform a radical but fertility preserving resection of extensive endometriosis with involvement of surrounding organ systems, realizing a good clinical outcome with low complication and recurrence rate, a very good improvement of QOL and a high pregnancy rate. However, for future research evaluating surgical treatment of extensive endometriosis, it is important to reach agreement on study design and on reporting clinical outcome data. A multicenter study with clear patient identification and well defined outcome parameters needs to be set up. Moreover, prevention of DIE with colorectal extension is important, ideally by early identification and management of girls and women at risk. Years of pain and disability as well as a lot of money could be saved when patients, at risk of developing extensive forms of endometriosis could be diagnosed during adolescence.