The abundance of interdisciplinary studies of coral reef metabolism means that coral reefs are amongst the best understood of marine benthic communities in terms of the determinants of primary production and nutrient fluxes, and their variation, at different levels of integration. Recent work has extended our understanding of the variation in coral reef productivity at different spatial and temporal scales. Nutrient limitation of production at scales ranging from the organism to the ecosystem is one of the most important topics of research at present, the relevance of which extends well beyond the tropics.