The field of advanced distributed simulation (ADS) has emerged and evolved since the 1980s. Developments are driven largely from within the United States (US) Department of Defense (DoD). This paper summarizes the history and evolution of ADS, detailing recent developments, notably the high level architecture (HLA). The implications of the HLA for data collection and analysis are discussed. Current approaches are reviewed including one of the largest ADS projects to date, the synthetic theatre of war (STOW), and its approach to data collection. We consider the impact of ADS beyond military training and discuss future development of ADS technology.