This is going to be a talk: mostly about time sharing, a little bit about the implications for management and an even smaller bit about the implications for management science. Not that these implications are minor. On the contrary, I think time sharing is going to produce profound, irreversible changes in both the practice and the science of management. But instead of the usual inspirational harangue on the revolutionary future that time sharing will bring, let's take a close look at the technical and economic fundamentals which define the invention and the necessity that it answers. Once these fundamentals are clear, you can make your own forecasts.