The High Energy Astrophysics Science Archive Research Center, HEASARC, is located at the NASA Goddard Space Flight Center in Greenbelt, MD (USA) and its activity is a joint effort between the Laboratory for High Energy Astrophysics (LHEA) and the National Space Science Data Center (NSSDC). HEASARC was created in 1990 to archive and provide access to data from high energy astrophysics missions. As of June 1994 some 125 databases were available. Most of the databases contain data from high-energy astrophysics missions such as EXOSAT, Einstein, Ginga, GRO (Compton), HEAO-1, ROSAT, ASCA (formerly ASTRO-D), BBXRT and XTE, while others contain well-known ground-based catalogs (see Tyler (1994) for a list). Users can sort, search, plot database entries, and cross-identify between these data sets. Telnet to legacy.gsfc.nasa.gov (128.183.8.233) and login as user xray (no password). For help on batch-processing of large lists of coordinates, names, and other time consuming queries, send an empty e-mail message to hdbreq@legacy.gsfc.nasa.gov. First-time users will be asked to give a HEASARC username, which will be used to allocate a user directory where files can be kept for use in subsequent sessions. Similar services are offered at three other sites in Europe: HEADS-Brera (see above), ESTEC in The Netherlands (see §3.2.4.), and Leicester (for UK users only). The HEASARC also publishes a newsletter called ``Legacy''; contact K. Smale at ksmale@lheavx.gsfc.nasa.gov to be added to the mailing list. [References: Tyler (1994).]