The burgeoning significance of coastal and maritime tourism to the global economy necessitates an innovative approach to marketing and operations management, particularly in the context of digital transformation and environmental sustainability. This paper presents a comprehensive investigation into the application and impact of Key Performance Indicators (KPIs) in enhancing the strategic management of coastal and maritime tourism destinations. Through a mixed-methods research design, incorporating both quantitative and qualitative analyses, the study examines the role of KPIs in optimizing marketing strategies, promoting environmental sustainability, and fostering community engagement. Findings reveal that specific KPIs related to guest satisfaction, digital engagement, and environmental performance are pivotal in driving marketing efficiency, operational excellence, and sustainable tourism practices. Case studies from diverse geographical regions underscore the adaptability and effectiveness of KPI-driven strategies across different market conditions and tourism models. The study contributes to the theoretical discourse on tourism marketing and management by integrating digital innovation with sustainability principles, offering actionable insights for practitioners aiming to achieve competitive advantage and sustainability in coastal and maritime tourism. The paper concludes with a call for the adoption of a comprehensive KPI framework, emphasizing the critical role of data-driven decision-making in navigating the complexities of the modern tourism landscape.