NGC 2000.0 is a modern compilation of the New General Catalogue of Nebulae and Clusters of Stars (NGC), the Index Catalogue (IC), and the Second Index Catalogue compiled by J. L. E. Dreyer (1888, 1895, 1908). The new compilation of these classical catalogs is intended to meet the needs of present-day observers by reporting positions at equinox B2000.0 and by incorporating the corrections reported by Dreyer himself and by a host of other astronomers who have worked with the data and compiled lists of errata. The object types given are those known to modern astronomy. The catalog lists object ID, object type, positions in equinox B2000.0, source of modern data (see NGC 2000 paperback copy), constellation, object size, magnitude, and the description of the object as given by Dreyer. The order of the new catalog is strictly by right ascension, the NGC and IC objects being merged into one machine-readable file.