This paper looks at changes in macrosociological paradigms for social development that traditionally stretch from the primitive society through the stratified medieval society to the image of a functionally differentiated modern society. Changing the perspective from a systems theoretical view of societies to an actor perspective, I focus on populations of individual actors and organizations as collective actors. Over recent decades, important structural changes in the nature of populations and of organizations have taken place in the Western world. The most important relate to economic globalization and financial internationalization. An increasingly flexible population and narrowly goal-specific organizations produce a situation of societal instability that appears to characterize the present, though its causes reach back half a century.