The Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo interferometric gravitational-wave detector of the European Gravitational Observatory (EGO) near Pisa, Italy, have agreed to join in a collaborative search for gravitational waves from sources in and far beyond our galaxy. The collaboration will link the three LIGO detectors, which are in the United States, and LIGO's partner, GEO600 in Germany, with the Virgo detector to increase the likelihood of detecting the elusive phenomenon first predicted over 90 years ago by Albert Einstein in his general theory of relativity, and pinpointing the source of the signals.