The HEASARC has served as NASA's archive for cosmic X-ray and gamma-ray datasets for 13+ years. In addition to this role, it has developed (FITS) data formats for the various files types found in these fields, and both general, e.g., FITSIO, and specialized, e.g., XSELECT, software packages to manipulate and analyze these data, as well as a variety of (primarily) Web-based tools to help scientists at all stages of the research process. I will discuss how the HEASARC is adapting its services to the challenges of new missions, such as Swift (Oct 2004 launch), Astro E-2 (Feb 2005), and GLAST (Feb 2007).