Visual Interactive Simulation (VIS) has dominated discrete-event simulation in the United Kingdom throughout the eighties. Conceived and initially implemented by Hurrion, who also coined the phrase, VIS first gained widespread exposure through the package SEE-WHY. The ideas behind VIS are fundamentally different from what is referred to in the United States as animation, since the prime motivater is user interaction with the running simulation, rather than just portrayal of the simulation. This paper presents a short history of VIS, and discusses some of the research and development that has been undertaken in the the United Kingdom and North America. Following presentation of an example of VIS, the state of VIS is discussed, and a number of generally accepted guidelines for doing VIS are presented. a number of recent developments in VIS, many of them also relevant to animation, are discussed, and four major issues in the research and practice of VIS are presented.