A series of biennial reports from the U.S. National Research Council have reviewed the progress of CERP. The fourth report in the series, released in 2012, found that little progress has been made in restoring the core of the remaining Everglades ecosystem; instead, most project construction so far has occurred along its periphery. The report noted that to reverse ongoing ecosystem declines, it will be necessary to expedite restoration projects that target the central Everglades and to improve both the quality and quantity of the water in the ecosystem.