Wellness and medical tourism (WMT) is part of the health tourism segment, which has been receiving considerable attention from domestic and international tourists. Thus, this chapter aims to discuss the situation of WMT in Thailand and ways to sustain a competitive advantage. Thailand has an excellent healthcare system. Tourists’ consumption of wellness products and services, including spas, massages and meditation, is gradually becoming a part of travel activities and experiences. In the meantime, medical tourism involves professional medical staff with state-of-the-art medical facilities and services in private hospitals and clinics. WMT markets are widely open in major travel cities across Thailand, such as Bangkok, Chiang Mai, Phuket and other second-tier cities. Thai government will continue to promote and ensure that local citizens and international tourists can optimise the benefits of WMT. However, at present, Thailand has been facing many challenges in maintaining competitive advantages in WMT markets from international tourists. Several recommendations are discussed for future improvements.