The paper offers a theoretical advancement on sustainable port development strategies adopting a relational perspective, emphasizing the importance of collaboration and stakeholder interaction in achieving sustainable value creation. It provides a comprehensive overview of the concept of value creation, highlighting its evolution and the different perspectives of analysis in business model research: the conventional value creation perspective, where customers and suppliers are considered key stakeholders in the supply chain, and the sustainability-oriented one, which extends value creation processes to other stakeholders, such as civil society, policy makers, financial stakeholders, and employees. Based on the main gaps of the literature review and drawing on the previous progress on the sustainable business model, this paper develops a theoretical framework, which structures the relationships between the port business operator and its stakeholders at two interconnected levels: the supply chain and the institutional environment. These levels identify core value creation activities and resources, relational governance models, and the value created with and for different stakeholders. However, its implementation opens new avenues for future research that are currently lacking in port research.