Progesterone (P4) plays an essential role in female reproduction and progesterone receptor (PR) agonists have been used in female contraceptives and in postmenopausal hormone therapy. Recent studies in women and non-human primates show that PR antagonists may also have potential as contraceptive agents and for the treatment of various gynaecological and obstetric diseases, including fibroids, endometriosis and, possibly, hormone-dependent cancers. Clinically available PR agonists and antagonists are steroidal compounds and often cause various side effects due to their functional interaction with other steroid receptors. Recently, numerous receptor-selective non-steroidal PR agonists and antagonists have emerged. This patent review will focus on the latest developments in these areas (since 2000).