The Combined Array for Research in Millimeter Astronomy (CARMA) was formed from the merger of three telescope arrays supported by the Division of Astronomical Science's University Radio Observatories (URO) Program: Caltech's Owens Valley Radio Observatory (OVRO) array of six 10.4-meter-diameter telescopes, the Berkeley Illinois Maryland Association (BIMA) array of nine 6.1-meter-diameter telescopes, and the University of Chicago's Sunyaev-Zeldovitch Array of eight 3.5-meter-diameter telescopes. CARMA currently achieves resolutions as high as 0.2 arcseconds at a wavelength of 1mm and, due to its heterogeneous combination of telescope diameters, provides excellent imaging over a wide range of angular scales. Science enabled by CARMA covers a broad range of astronomical topics, including star formation and molecular clouds, studies of external galaxies, and the investigation of solar system objects. CARMA is a pathfinder for the Atacama Large Millimeter Array (ALMA) and a pipeline for training experts in the field of millimeter interferometry to take full advantage of ALMA's capabilities for US astronomy. Users outside the CARMA collaboration receive 30% of all observing time.