Purpose: This paper entails a reflection on sustainability and specific tourism contexts (i.e., ecotourism). It focusses mainly on local communities’ determiners in the consumer’s purchase decision process in ecotourism. This research aimed at understanding the determiners in the process of consumer decisions in ecotourism contexts, as well as verifying the growing importance of ecotourism. Methodology: A questionnaire was conducted (with ecotourism specific contexts), in Portugal. Portugal is a tourist destination that has gained notoriety and recognition in recent years. In total, 197 questionnaires were collected, aiming for a deeper understanding of the real social, economic, cultural and environmental impacts resulting from the uncontrolled development of tourism. This study aimed at testing the proposed conceptual model empirically (i.e., the relationship between destination image and post-purchase behaviour). Findings: Sustainability must be looked at as a vital need for society in general, as well as for the tourism sector. Ecotourism is the natural evolution of tourism employing care for the environment, culture and local traditions, while promoting environmental education. Research Limitations: The results obtained are limited, considering the availability of most accommodation units in the ecotourism segment in Portugal (e.g., hotels). As next steps, it is advisable that hotel units come to realise the pertinence of such research as they are the main beneficiaries of these initiatives, being then recommended that they collaborate with the process of completing surveys. Originality/Value: Managers and ecotourists can use the outcomes of this study to gain an in-depth understanding of customer experiences (i.e., sustainability experiences), to develop effective marketing strategies, and to create an operational environment that can maximise customers’ perceived experiential values. Destination image plays a fundamental part in terms of experience and the tourist’s own satisfaction, with a need to improve the degree of affectivity towards the hotel unit.