The ever-expanding depth and quality of photometric and spectroscopic observations of stellar populations increase the need for theoretical models in regions of age-composition parameter space that are largely unexplored at present. Stellar evolution models that employ the most advanced physics and cover a wide range of compositions are needed to extract the most information from current observations of both resolved and unresolved stellar populations. The Dartmouth Stellar Evolution Database is a collection of stellar evolution tracks and isochrones that spans a range of [Fe/H] from–2.5 to+ 0.5,[\alpha/\mathrm {Fe}\,] from–0.2 to+ 0.8 (for [\mathrm {Fe}\,/\mathrm {H}\,]\leq 0) or+ 0.2 (for [\mathrm {Fe}\,/\mathrm {H}\,]> 0), and initial He mass fractions from Y= 0.245 to 0.40. Stellar evolution tracks were computed for masses between 0.1 and 4 M_ {\odot}, allowing isochrones to be generated for ages as young as 250 Myr. For the range in masses where the core He flash occurs, separate He-burning tracks were computed starting from the zero age horizontal branch. The tracks and isochrones have been transformed to the observational plane in a variety of photometric systems including standard UBV (RI) _ {\mathrm {C}\,}, Stromgren uvby, SDSS ugriz, 2MASS JHK_ {s}, and HST ACS/WFC and WFPC2. The Dartmouth Stellar Evolution Database is accessible through a Web site at http://stellar. dartmouth. edu/~ models/where all tracks, isochrones, and additional files can be downloaded.