Book excerpt: Human-System interaction has been and will continue to be of interest to many researchers of various disciplines: engineers, computer scientists, psychologists, and social scientists. The research in Human-System Interaction (HSI) has progressed from the era of using anthropomorphic data to design workspace to the current period which utilizes human and artificial sensors to design sensory-based cooperative workspace. In either of these developments, HSI has been known to be complex. In 1994, we initiated a series of symposiums on Human Interaction with Complex Systems. It was then that various ideas surrounding HSI for today and tomorrow were discussed by many scientists in the related disciplines. As a follow-up, in 1995 the Second Symposium was organized. The objective of this symposium was to attempt to defme a framework, principles, and theories for HSI research. This book is the result of that symposium. The 1995 symposium brought together a number of experts in the area of HSI. The symposium was more focused on expert opinions and testimonies than traditional meetings for technical papers. There were three reasons for that approach.