The paper presents an aggregated (five sector) circular flow model of economic development. A key concept, the "societal technology" implicitly, by means of a stratified dynamical system, describes the alternative paths of development that are open to a society. Societal objectives, which determine the actual path, can enter in both a purely descriptive, positive way and as normative "planner's preferences". The aim of the paper is to provide a conceptual basis for the investigation of long-term socioeconomic processes with the tools of dynamical systems theory.