This article draws on research undertaken at Monash University for my Ph.D. thesis, ‘Musical and functional change in the gondang sabangunan tradition of the Protestant Toba Batak 1860s–1990s with particular reference to the 1980s–1990s’ (1999). I am greatly indebted to countless individuals in North Sumatra and Australia whose generous assistance made my research possible. I wish particularly to thank those gondang musicians and ministers of both the Protestant and Catholic Churches who shared with me their knowledge of the gondang tradition, and of adat and Christianity in Toba Batak society. I am grateful to R. M. Naipospos, the leader of the Parmalim community, who allowed me to attend the Parmalim Sipaha Lima ceremony, from which I learned much about the pre-Christian Toba Batak belief system and the performance of gondang and tortor in the context of religious ceremonies. I am most indebted to my supervisor, Margaret Kartomi of the School of Music-Conservatorium at Monash, for critical readings of this article, advice and encouragement; Kay Dreyfus at Monash for valuable research and editorial help; and Yoshiko Okazaki and Rob Hodges for their very helpful critical readings of the drafts.