Endometriosis is a painful reproductive and immunological disease afflicting about 7-10% of women worldwide. It is one of the most frequent benign gynaecological diseases; however, little is known about the pathogenetic processes leading to the development and maintenance of this disease and the currently available therapeutic strategies are unsatisfactory. The goal of this article is to review the most recent advancements in the pathogenesis, diagnosis and therapy of this disease. The risk for cancer among women with endometriosis will be analyzed in light of the most recent epidemiological and functional studies focused on this disease.