In the global scale, policymakers have increasingly prioritized sustainable tourism development as a core objective, seeking to harmonize economic expansion with ecological preservation and the safeguarding of cultural and social heritage. This study seeks to clarify the relationships among sustainable tourism policies, destination management, social responsibility of destinations, and tourists' value orientation toward sustainable tourism development. Data were collected through a cross-sectional survey comprising 500 valid responses from tourists, local government, firms in tourism, tour guides, and specialists in tourism in Vietnam, and structural equation modeling (SEM) was employed to test the research hypotheses. The results indicate that sustainable tourism policies, destination management, and destinations' social responsibility significantly and positively influence sustainable tourism development. Notably, social responsibility partially mediates the relationship between policy/destination management and sustainable tourism development. These findings offer practical managerial implications for devising sustainable tourism strategies, optimizing economic benefits while protecting the environment and preserving the socio-cultural values of destinations