XMM-Newton, the X-ray Multi-Mirror Mission, is the second cornerstone of the Horizon 2000 program of the European Space Agency (ESA). XMM-Newton was launched on December 10 1999 at 14:32 GMT (09:32 EST). The observatory consists of three coaligned high throughput 7.5m focal length telescopes with 6 arc second FWHM (15 arc second HPD) angular resolution. With its large collecting area and X-ray and optical/UV bands, XMM greatly facilitates studies of objects ranging from clusters of galaxies to compact objects, and their inherent physical attibutes. Besides having funded elements of the XMM-Newton instrument package, NASA also provides the NASA Guest Observer Facility (GOF) at the NASA/Goddard Space Flight Center (GSFC) and funds a Guest Observer (GO) program to support the usage of XMM by the U.S. scientific community. The GOF provides a clearing house for project-generated technical information and analysis software as well as budget support for U.S. astronomers who apply for XMM-Newton observation time.