This study involved a comprehensive investigation of the sea-grass habitat of the eastern Gulf of Mexico between St. Andrews Bay and Fort Myers, Florida, to determine its potential as a nursery area for the production of economically important reef-fish species that have estuary-dependent juvenile stages in their life histories, particularly gag grouper and gray snapper. The objectives of this work were (1) to develop recruitment indices for gag grouper, gray snapper, and other sea-grass-recruiting juvenile reef fish in the eastern Gulf of Mexico; (2) to describe spatial and temporal utilization patterns and ecological relationships of selected sea-grass-recruiting juvenile reef fish; and (3) to determine habitat suitability of various sea-grass habitats of the eastern Gulf of Mexico to selected juvenile reef-fish species. We accomplished these objectives by delineating and characterizing the habitat and community structure of major shallow-water sea-grass community types in the study area; (2) by describing spatial and temporal changes in habitat characteristics and community structure, including utilization patterns of selected reef-fish species; (3) by determining the absolute abundance of selected economically important reef fishes relative to sea-grass community types; and (4) by describing movement patterns of selected reef-fish species within the estuarine environment and during egress from it.