Preserving Virtual Worlds II: Methods for Evaluating and Preserving Significant Properties of Educational Games and Complex Interactive Environments (PVW2) was conducted in partnership with the University of Illinois (lead institution), the Rochester Institute of Technology, and Stanford University. The goals of PVW2 were to help improve the capacity of libraries, museums, and archives to preserve computer games, virtual worlds, and interactive fiction. The work was funded by a $785,000 National Leadership Grant awarded by the Institute of Museum and Library Services. MITH’s research team played a major role in all aspects of the new project, including content analysis work, interviews with game players and producers, and conducting double-blind studies to help evaluate the “significant properties” of games and other interactive media. PVW2 was a novel methodology for studying the significant properties of video games and other complex interactive environments. By focusing on the temporal transitions between developer versions and player mods, PVW2 identified patterns of stability and change in game attributes–such as graphics, text, sound, items, and sprites–in order to help infer how different communities of practice interpret their relative significance.