Abstract. – Notions of water, both as symbol of purity and means of purification, are evidenced in many Lahu ritual activities. Simultaneously, bodies of water and waterways are considered to be the abode of owner-spirits that may cause harm to those who infringe on their aquatic domain without first exercising sufficient respect and/or propitiation. Exposure to Buddhism has brought with it an overlay of Indic notions concerning water, particularly notable among which is the custom of ritually pouring water onto the earth as a means of transferring the merit of a person’s gift-giving to others, either living or dead. Lahu attitudes towards water and its use in ritual are among many facets of the Lahu cultural heritage that exemplify a synthesis of animist, theist and Buddhist ideas and practices. This situation serves to remind us of the dangers inherent in categorizing mountain peoples, such as the Lahu, as altogether distinct from their politically-dominant lowland neighbors in the Yunnan-Northern Southeast Asia borderlands. [Southeast Asia, Tibeto-Burman peoples, the Lahu, animism, theism, ritual, Buddhism, religious syncretism]