Industrial agriculture is the highly volatile, capital-intensive food production system characteristic of industrial societies. This article will explore the characteristics of this form of agriculture and will use ecological and bioenergetic perspectives to interpret the current crisis in the U.S. farm sector. Evolutionary theorists in this area have tended to focus on the level of the total system, while this analysis will include the actor level as well (see Paul, this volume). Although the conditions of U.S. agricultural production are highly determined by the state and by other aspects of the economic context, different family traditions and farm strategies nevertheless play an important role in balancing among diverse pressures for maintaining tradition and for change. The current farm crisis may result in an escalation of the volatility and instability of U.S. agriculture, or it may begin the process of evolution to a more stable food production system. When viewed from the ecological and cultural evolutionary perspective in anthropology, human subsistence modes have evolved in two general directions: toward labor and capital intensivity. Responding to the imperatives of population pressure and elite surplus extraction (see Brown, this volume) and the desire to produce a surplus for exchange, human groups have developed more productive means of obtaining food under less favorable conditions (Barlett 1974, Boserup 1965, Polgar 1975, Service 1975). Agricultural evolution can be conceptualized as a process of intensification of resource use and capture of energy (Adams 1985; Bennett 1976; Rappaport 1979; Wilkinson 1973). A continuum of increasing total output and labor intensity per land unit can be seen in the evolution from swidden systems to plow agriculture and irrigation agriculture (Netting 1974, 1977). Industrial agriculture can be placed at the end of this continuum in terms of total resource and energy use; in other ways, it deviates from this evolutionary line. Productivity per land unit is less important than productivity per labor unit, and land is often used extensively. The hallmark of industrial agriculture is capital intensification and heavy investment in machinery and purchased industrial inputs. In the United States, industrial agriculture emerged out of initial conditions of abundant land, scarce labor, high soil fertility, favorable weather, available capital, and abundant energy resources in trees, water, minerals. Later, a dominant position in international trade aided the capture of energy from other world