<jats:p>Social media are transforming relationships with customers for all sectors, including tourism. Since the search for information is a critical aspect of tourist purchase decision process, the importance of social media for tourism is evident. However, the presence of tourism brands in social media is not enough to have an impact on tourist purchase decisions: it is necessary to generate engagement. This chapter aims to conceptualize tourist engagement on social media and identify tourist engagement indicators. Tourist engagement was conceptualized through a literature review that identified four dimensions of engagement: popularity, commitment, virality, and post engagement. A set of indicators is proposed to measure tourist engagement in each of these dimensions. The proposed TSM engagement framework was validated through a mixed-method approach, using secondary data and interviews carried out with Brazilian tourist destinations. </jats:p>