The pre-history of SISO starts with SIMNET, a DARPA program from 1983 through 1991 that demonstrated the feasibility of networking substantial numbers of (relatively) low-cost simulators on a "virtual battlefield." Based on the success of this program, the US Army initiated a large-scale program called Combined Arms Tactical Training. In order to ensure that multiple teams of contractors would be able to bid on various components of this program, the Army Program Manager for Training Devices (PM TRADE), soon to be renamed as the Army Simulation Training and Instrumentation Command (STRICOM), in conjunction with DARPA and the newly established Defense Modeling and Simulation Office (DMSO), initiated a series of workshops at which user agencies and interested contractors could work together to develop standards based on the SIMNET protocols. The "First Conference on Standards for the Interoperability of Defense Simulations" was held on 22-23 August 1989 in Orlando, Florida.

DIS Workshops were held semi-annually from 1989 through 1996. The first Simulation Interoperability Workshop (SIW) held under the SISO banner was the 1997 Spring SIW in Orlando. SIWs have continued semi-annually since 1997. In 2001, SISO also began holding annual Euro-SIWs at various locations in Europe. A schedule of SIWs is maintained on main in our Workshops area.

In 2003, the IEEE Computer Society Standards Activities Board (SAB) granted the SISO Standards Activities Committee (SAC) status as a recognized IEEE Sponsor Committee. SISO now maintains two major families of IEEE standards, IEEE 1278 (Distributed Interactive Simulation) and IEEE 1516 (High Level Architecture for Modeling and Simulation). These standards were initially developed by members of the DIS/SISO organization acting as a subcommittee of the IEEE Computer Society SAB.