The Probing Lensing Anomalies NETwork (PLANET) collaboration coordinates a network of telescopes to rapidly sample photometric measurements of the magnification of stars in the galactic bulge undergoing gravitational microlensing by intervening foreground stars. This network consists of five 1m-class optical telescopes distributed in longitude around the Southern Hemisphere in order to perform quasi-continuous round-the-clock precision monitoring. On a target-of-opportunity basis, less frequent spectroscopic measurements complement the rapid photometry for selected prime targets. Since 2005, PLANET performs a common microlensing campaign with RoboNet-1.0, a network of UK-operated 2.0m robotic telescopes.