In December 2011, the National Nuclear Data Center released ENDF/B-VII.1, the “latest recommended evaluated nuclear data file for use in nuclear science and technology applications.” The data were released in the standard Evaluated Nuclear Data Format (ENDF). This release represents the advances made in nuclear data during the 5 years since the release of ENDF/B-VII.0. The Nuclear Data Team at Los Alamos National Laboratory has processed the ENDF/B-VII.1 library and made available a library of ACE data tables at several temperatures for each of the ENDF/B files. The ACE data library is called ENDF71x and is available through the Radiation Safety Information Computational Center with MCNP6. The files can also be used with MCNP5 or other Monte Carlo codes.