© 2011 Elsevier Inc. All rights reserved. Hypoxia is one of the greatest threats to coastal zone ecosystems, where in extreme cases vast dead zones result. Primary drivers of hypoxia include nutrient loading from anthropogenic sources and physical processes that lead to stratification. Models are useful tools for the study of hypoxia. Their frameworks, however, vary tremendously ranging from simplified portrayals of biota and the physical environment (productivity and metabolism simulated in a box model) to complex food-web representations within three-dimensional circulation schemes. Much knowledge has been gained through the study of simple models. However, to further our understanding of factors influencing hypoxia, the development of additional complex models followed by an analysis of similarity in their qualitative behaviors is needed.