There has been increasing interest in the use of humour in patient care within recent years. However, little research has been conducted to show the natural utilisation of humour, particularly from the participants' perspective, within the clinical environment. This study uses ethnomethodological ethnography and conversation analysis methods to investigate the use of humour between nurses and patients with renal failure who were learning about, and to, haemodialyse. It is believed that the project is unique in the utilisation of audiovisual video recordings to measure and describe the frequency, distribution and use of humour. Findings indicated that humour rates and the proportion of humour produced by the patients were differentially distributed between patients but, overall, not between the same patients on different occasions. In addition, in one case a significant positive relationship between the rate of humorous instances per session and time was demonstrated and another patient (D) was found to produce a significantly larger proportion of the humour over time. Further exploration of patient D's increasing use of humour revealed that one important aspect was associated with the patients anxiety and difficulties with regard to ‘needling’. The findings have implications for understanding the role of humour in health care communication, particularly with reference to developing formal ‘humorous interventions’.