We are all accustomed to statistics about how many people live near the coasts (53% living within U.S. coastal counties; 75% globally within 100 km of the coast); however, it is also becoming clear that among the types of coastal environments most threatened by social and natural stresses, shallow-water environments are particularly susceptible. Clear-water environments (e.g. coral reefs) lie at one end of the shallow-water spectrum; and muddy-waters at the other. While corals have seen increasing attention from the science and management communities in recent years, this volume focuses on the muddier end of the spectrum. In the preface to this new book from Elsevier’s “Proceedings in Marine Science” series, the editors define these muddy coasts as “land-sea transitional environments commonly found along low-energy shorelines which either receive large annual supplies of muddy sediments, or where unconsolidated muddy deposits are being eroded by wave action.” These areas, representing vast expanses of mangroves, salt marshes, and shores of estuaries and lagoons, are threatened not only from direct (e.g. fishing, aquaculture) and indirect (agriculture, development) human use and, but also from the slowly encroaching sea caused by increasing rates of sea level rise.