This paper provides background information and a brief overview of water quality issues for the rest of the papers in this volume that are concerned with Everglades restoration. The Everglades of Florida have been diminished over 50% of their former extent. The Everglades are no longer a free-flowing wetland ecosystem, but are now subject to a complicated system of water management that is regulated primarily for flood control and consumptive use. Attempts to restore a more natural hydropattern to the remaining undeveloped Everglades are made more difficult by the natural extremes in rainfall, flat landscape, highly porous geology, and inaccessibility of the remaining natural areas. The Comprehensive Everglades Restoration Plan (CERP) seeks ecosystem restoration by adding water storage capacity, reducing groundwater seepage, improving regulatory delivery and timing of water to avoid environmental damage, and where feasible, improving the quality of water to be used for Everglades restoration. Water quality issues that currently exist for south Florida include eutrophication (especially phosphorus), mercury, and contaminants from agricultural production and the urban environment. Lands once in agricultural production that will be converted back to wetlands or will become reservoirs may contribute to the water quality concerns. Stormwater runoff from managed lands that will be used for restoration purposes will also present water quality challenges. The state continues to seek water quality improvement with a number of pollution reduction programs, and CERP attempts to improve water quality without sacrificing even more natural areas; however providing water quality sufficient for use in recovery of remaining Everglades wetlands and estuaries will remain a daunting challenge.