Mystery orchid from AOS site

Does anybody know what type of orchid this is? It's one of the beautiful pictures that the American Orchid Society uses on their web site. This flower is great - I love the "lips" especially!

One of the many helpful sections on the AOS web site is called Monthly Checklist. You can find it under Orchid Information and can read about a number of genera and tips for caring for them for September / October. If you have any strange spots or discolouration appearing on the leaves of your orchids, take a look at the Orchid Doctor section, also under Orchid Information.