Overview: The Two Micron All-Sky Survey (2MASS) is a near-infrared digital imaging survey of the entire sky conducted by the University of Massachusetts and IPAC at 1.25, 1.65 and 2.17 microns. A pair of matched 1.3-m diameter telescopes (Arizona and Chile) completed survey operations in early 2001. Data processing and product development continued through 2003. Key science goals of the survey include the large-scale structure of the Milky Way and the Local Universe, an accurate census of stars in the solar neighborhood, and the discovery of new brown dwarfs and active galactic nuclei.