Economic development has long been a dominant topic in sociology. Since Marx' and Weber's initial insights, sociologists have been unraveling the complex relationships in this ubiquitous process. Recent conceptual work (Smelser, 1959, 1963; Parsons, 1966; More, 1964; Eisenstadt, 1964, 1965; Rostow, 1963) has attempted to isolate critical variables and relationships among them in the process of economic development. One of the consistent attempts of this literature is predicting when, where, and how fast economic development will occur in modernizing Third World nations. Drawing upon this growing body of literature, this paper will outline an analytical model of economic development. This model is especially relevant to developing Third World nations, although it is sufficiently abstract to encompass economic development in other types of historical and contemporary societies. The term model has an ambiguous meaning. In this paper, a model is a map or grid of relationships among analytically important units. The model presented here is cybernetic, denoting key feedback processes, both negative (Weiner, 1954; Nadel, 1953) and positive (Maruyama, 1963). Ideally, a model should assign differential weights to various relationships, but in the model to be presented, only general weights will be assigned to some relationships. As will be emphasized, feedback relationships among units will be considered to carry more weight than other relationships in determining rates of economic development. Beyond this, existing data do not warrant further weighting. But an attempt will be made to delineate those variables within and outside the economy affecting the weights of any particular relationship in the model. In doing so, elements in the model can begin to approximate a set of propositions in a more general theory of economic development. For the purposes of analysis, the economy can be divided into two general sectors (Moore, 1967): (1) the productive; and (2) the distributive. Production concerns those structures and processes involved in gathering resources from the environment and converting them into goods and commodities, while distribution refers to those structures and processes dealing with the dissemination of commodities throughout a social system. The model presented in this paper will focus on relationships between and within these two general economic sectors. [ABSTRACT FROM AUTHOR]