The purpose of this workshop is to identify important hydro- and ecological relationships that will affect the ability of floodplain managers to optimize their approaches to providing: 1) fish habitat; 2) wildlife habitat; 3) nutrient and sediment processing; and 4) flood regulation. The resulting conceptual model will guide future floodplain science, including the development of numerical simulation models of high interest relationships. Twenty participants at the workshop included science experts on each of the four floodplain functions, policy analysts, and floodplain managers faced with making optimization decisions. The workshop report will focus on relationships of greatest need of quantification and how they would be affected by common or anticipated new management practices. The workshop was jointly sponsored by the Illinois Natural History Survey, the Eastern Tallgrass Prairie and Big River LCC, the USGS/LRI, and unless there are objections, the FpSN. The workshop was held at the National Great Rivers Research and Education Center (NGRREC) on July 29-31, 2014.