Over the past thirty years, the global tourism industry has significantly contributed to economic growth and job creation. However, this rapid expansion has also led to substantial environmental challenges, including increased carbon emissions and the depletion of natural resources. This study examines the impact of sustainability on tourism, using Spain as a case study to illustrate effective strategies and outcomes. Spain’s commitment to sustainable tourism, reflected in initiatives like the Sustainable Tourism Strategy 2030, emphasizes biodiversity conservation, pollution reduction, and community engagement. Through content analysis of academic and managerial sources and in-depth interviews, the study identifies a positive relationship between sustainable tourism practices and tourist preferences, indicating that destinations prioritizing sustainability attract more visitors, including those who are willing to pay premiums for eco-friendly experiences. The integration of sustainable practices not only improves environmental quality but also contributes to economic growth by boosting tourism revenues and stimulating local investments in sustainability. Therefore, this research contributes to understanding how sustainable tourism can achieve a balance between economic development and environmental stewardship.