A documentation research project to study the complex issues facing the historical documentation of multi-institutional collaborations in physics and allied sciences. Phase III focused on four disciplinary areas of ground-based astronomy, materials science, heavy-ion physics, and medical physics, and a category named computer-mediated collaborations. Sagittarius-A was a collaboration of MIT Haystack Observatory, the University of California, Berkeley Hat Creek Observatory, the California Institute of Technology Owens Valley Observatory, the National Radio Observatory, the National Radio Astronomy Observatory, and the Harvard-Smithsonian Center for Astrophysics (1994-1996) to observe an intense radio source through VLBI at 3.5 mm wavelength. The collaboration had no physical location; it used the antennae at Owens Valley, Kitt Peak, and Haystack. Eleven scientists participated. The collaboration itself was not explicitly funded, but the member organizations had funding from NSF or NASA. The collaboration has disbanded, but can reconstitute itself.