Archaeological data that show radically increased levels of consumption are combined with economic theory regarding population, technology, and economic growth. The purpose of this exercise is to understand both the scope and constraints of per-capita income, living standards, and consumption in a context of population growth. Malthusian models on economic and demographic developments in preindustrial societies have been fiercely debated by economic historians working on later periods. The fixity of land and the diminishing returns to labour were indeed constraining factors, but the more important factor was the ability of the economy to respond positively to the stimulus of population growth. The role of technological changes should not be overestimated, though. The most important technological progress in the Roman world does not concern new inventions, but the wider implementation of knowledge that had been available for centuries. Investment in human capital and innovation were no obstacles, as they were responses to rather than causes or preconditions of economic growth. An increase in output in the Roman economy can to a large extent be explained by the transfer of underemployed agricultural labour to more intensively utilized urban and rural non-agricultural labour. Against prevailing Malthusian views, it is argued that a significant rise in per-capita income in the Roman world resulted in higher average living standards and different consumption patterns, which in turn significantly changed the conditions not only of manufacturing and trade, but also of investment and innovation.