Groundwater salinization in coastal regions poses a significant threat to water securitySecurity, ecosystemEcosystem health, and socio-economic development worldwide. This chapter provides a comprehensive analysis of the concepts, mechanismsMechanisms, impacts, and management strategies related to coastal groundwater salinization. It examines case studies from diverse geographical contexts, including the Mediterranean coastal areas, South Asian coastal aquifersAquifer, and the Gulf Coast of the United States, to illustrate the global scope and regional specificities of the issue. The chapter analyzes the interactionInteraction between natural hydrogeological processes and anthropogenicAnthropogenic influencesInfluences that drive salinization, emphasizing the need for integrated management approaches. It assesses the environmental, socio-economic, and health impacts of groundwater salinization, highlighting the far-reaching consequences for coastal communitiesCommunity and ecosystemsEcosystem. The various control mechanismsMechanisms were evaluated, including monitoring systemsSystem, engineering solutions, and policy interventions, and sustainable groundwater development strategies within the frameworkFramework of integrated water resourcesWater resources management were explored. Emerging technologiesTechnology and innovative approaches for enhancing coastal aquiferAquifer management are discussed, along with recommendations for future research and practicePractice. By synthesizing current knowledge and identifying key challenges and opportunitiesOpportunities, this chapter contributes to the broader understandingUnderstanding of coastal groundwater managementGroundwater management and promotes sustainable water resourceWater resources practicesPractice in the face of growing global challenges.