Change is the most pervasive characteristic of our time: technological change affects production, transportation, and living patterns, these in turn cause changes in existing ecological and social systems, these again influence decisions and behavior of the individual, and of the organizational entities at the various levels of the social system. It is these decisions and actions which control further change and with it the future living conditions on our planet. In many domains of our experience - production, consumption, construc­ tion, transportation - we have become accustomed to annual average rates of change of around five percent, or a doubling in 14 years. Yet the social and political problems all around us seem to indicate that individuals as well as social structures are ill-equipped to deal adaptively and construc­ tively with such rates of change - which may locally reach much higher values, such as 25 percent per year, or a doubling every three years. In many, if not most cases, such amounts require qualitatively different responses, or a constant review and adaptation of the normative principles controlling decision and action. Change is never isolated. It is the result of, and it causes, other changes.