Using the conceptual framework of ecoregional conservation, this thesis provides an assessment of the current conservation frameworks operating within the Northern Appalachian/Acadian Forest ecoregion. The ecoregion, which covers three provinces, four states and two countries, stretches from the Adirondack Plateau in New York, through northern New England, the Eastern Townships and the Gaspé Peninsula of Québec, and includes all of New Brunswick and Nova Scotia. Much of the ecoregion was severely deforested and exploited in the first 400 years of European settlement and has now reached another crossroads in its evolution as the landscape is subjected to a further surge of human-induced stressors and habitat destruction. The impacts range from urban and rural sprawl, unsustainable resource extraction, and habitat fragmentation related to road construction and development. A policy analysis, combined with interviews with conservation practitioners, is used to identify strengths and weaknesses within the existing policy regime and to develop an alternative model policy for ecoregional conservation. This Model Policy addresses the impacts of land use conversion, unsustainable resource extraction, and facilitates cooperation across borders by defining the baseline biodiversity conditions of the ecoregion, regulating land use and development, assessing cumulative impacts, and designating a connected network of protected areas.