Passed in 1971, Delaware’s Coastal Zone Act was a pioneering law that declared as public policy the prohibition of heavy industry and the regulation of manufacturing within Delaware’s coastal zone because of the environmental threats posed by such development. This article is the first comprehensive scholarly analysis of how the Act has been interpreted and applied to protect Delaware’s coastal environment. It provides an extensive analysis and annotation of how the Act’s terms have been used and the principles of statutory interpretation that inform the Act’s continued application. The article argues that the Act’s prohibitions on heavy industry and bulk product transfer facilities, as well as the requirement that manufacturing facilities “offset” their negative environmental impacts, can serve as a blueprint for any coastal state seeking to protect coastal natural resources. It concludes that, while the Act has been a success within Delaware, threats to its continued vitality exist and must be met by increased vigilance and fealty to the principles of interpretation that have guided it through its history