The Brazilian Coastal Zone (CZ), declared National Heritage, is endowed with strategic importance, constituting an area of expressive economic relevance, since coastal economic activities contribute significantly to the gross domestic product (GDP), largely due to the presence of ports that handle a substantial portion of export activities, and where more than a quarter of the Brazilian population lives, comprising 17 states and 443 municipalities. The objective of this chapter is to outline legal strategies for the effective management of Brazilian coastal environments and their adjacent oceanic area. This proposal is grounded in marine spatial planning (MSP) concepts and an analysis of the legal framework for protecting marine biome ecosystems and resources and the possible conflicts and planning actions, implementation, and compatibility of public policies related to the management of the CZ and MSP, especially with the Brazilian Bill 6.969/2013. Finally, the chapter presents the international MSP practices and the example of Portugal’s maritime space management and planning framework, which demonstrates, among other issues, the criteria used to determine the primary use or activity in cases where there is a conflict between different uses or activities in the national maritime space. Comparing with the Portuguese maritime territorial management model, it appears that Brazil does not have this regulation in its legal system but can include this model of legal strategy in the phases of the MSP pilot project in the southern region of the country. This demonstrates the objective of maintaining legal security, meeting political interests and strategies at sea, and promoting the environmental sustainability of oceans and coastal areas while strengthening the sovereignty of the Blue Amazon.