The Buddhist practice of cultivating mindfulness has been increasingly influencing psychotherapeutic work. However, in Sri Lanka, the documentation on the use of such practice in psychotherapy is scarce. This paper aims to discuss the influence of Buddhist mindfulness practice on psychotherapy; present a case of mixed anxiety-depressive disorder where mindfulness practice and behaviour therapy were used in its treatment and discuss issues that need to be considered in the use of mindfulness practice in psychotherapy. The combined use of Buddhist mindfulness practice and behaviour therapy yielded a favourable outcome in the case reported. In Sri Lanka, a culturally rooted method such as mindfulness practice, in combination with behaviour therapy, is useful in the treatment of mixed anxietydepressive disorder. The use of mindfulness practice in psychotherapy should be undertaken by those trained in psychological assessments and by those who have their personal mindfulness practice. Future studies on the use of mindfulness practice in other psychological disorders would be useful.