The present work is based on fieldwork carried out in Southern Sri Lanka among the Beravayo, a low status caste traditionally responsible for the performance of various ritual drumming duties. Although this occupational association goes back centuries and is still an important element in their contemporary caste identity, the Beraväyö are nowadays involved in a wide range of other ritual activitiea which include temple art work. astrology and in particular the performance of elaborate healing rituals for the relief of sickness and misfortune. The thesis centers on the lives and work of those Beraväyö who are most closely involved with the performance of such healing rituals. The first part of the thesis (Chapters 1-4) deals with the social organisation of the Beravä caste, paying particular attention to the way in which the various traditions of knowledge and skill which make their ritual performances possible are reproduced. The traditions passed on within the caste are viewed as a kind of property and the role they play in strategies of marriage and apprenticeship is examined. Chapter 4 deals with the translation of personal traditions into the caste specific services for which the caste is known. This entails examining the structure and organisation of the troupes which come together to perform certain rituals and the various factors, such as cost, scale of performance and elaborateness of preparations which the ritual patron must consider. The second part of the thesis (Chapters 5-7) deals with a specific ritual, an astrological ritual called the Bali Tovil which is intended to combat the malign influences of the planets. A description of the beliefs and ideas which underlie the ritual is given. followed by an account of a particular performance of a Bali Tovil. The analysis given in Chapter 7 attempts to account for the persuasive power which the performance of this type of ritual has in producing a positive effect on its participants. The final Chapter (8) looks at the impact of changes upon the tradition oriented system of ritual organisation and performance described in the previous chapters. The changes in question are coming from tourism and the new markets for cultural artefacts which this brings. With changes in the style of production to meet this demand, the meaning which various traditions have for those who possess them is re-evaluated. Chapter 8 demonstrates how traditions are creatively transformed to meet these changing circumstances and the consequences this has for the wider Beravä community.