Although humour is a key element of human communication, and, for this reason, it is also present in therapeutic contexts, its use in this sense still remains largely untapped. The purpose of this article is to increase curiosity and broaden the reflection on the use of humour in the psychotherapeutic relationship. The first part is dedicated to a short review of the main theories on the origins of laughter. The second part will examine those studies reporting a beneficial effect of humour on physical well-being, while the third part will review those studies describing how humour can help improve psychological well-being. The fourth part will further explore the clinical effects of humour in the therapeutic relationship. Both the positive and negative effects of humour in the therapeutic relationship will be discussed. In addition, some brief examples are included.