The interest and relevance of medical tourism has increased significantly over the last few decades, and it has become a very lucrative source of income and profit for many firms. This paper analyses the sustainability of the medical tourism model in Spain in general, and in The Costa del Sol (Spain) in particular, in order to investigate the potential challenges that the domestic industry will face in the future. For this purpose, we first analysed the process of the globalization of health services and the main characteristics of the Spanish medical tourism industry (in terms of tourism and health services). Second, we examined the data availability on medical tourism for the cases of Spain, Andalusia and The Costa del Sol, and identified who travels, why, and for what reasons. The results show that Spain and The Costa del Sol offer high-quality medical and tourism facilities and services with very competitive prices, and with the high commitment and support of public local authorities, tourism and health providers, and universities. However, the lack of a real leadership, well-defined strategy, financial support, and specific training programs are considered to be crucial challenges for the near future. In addition to this, the novel coronavirus, the economic crisis, Brexit and the situation of British expats living in Spain and The Costa del sol are also discussed.