The central theme of this selection of articles is a phenomenon that involves the emergence of religious groups in the Brazilian Amazon that build their systems of ritual, myth and principles around the use of a psychoactive brew known by several different names, one of which is the Quechua term ‘ayahuasca’. 1 These religions – Santo Daime (in its Alto Santo and CEFLURIS branches), Barquinha and the União do Vegetal – are generically labelled as ‘Brazilian ayahuasca religions’ in anthropological writings. Although the field of studies of these religious movements has seen much development in recent decades, there are still very few publications in English, especially in the area of anthropology. 2 This collection seeks to address this absence and offer visibility to the research conducted in Brazil, most of which has been carried out by Brazilian researchers. The current collection has attempted to select a representative sample of the main types of approaches that have been used. It also offers a view of the historical development of this field of research in Brazil, especially from the perspective of the human sciences, particularly anthropology. We have included articles previously published only in Portuguese, in compilations that one of us has also organized (Labate and Araújo 2004; Labate et al. 2008). This is the case of the articles by Mariana Pantoja Franco and Osmildo Silva da Conceição, Arneide Bandeira Cemin, Edward MacRae, and Wladimyr Sena Araújo. Some of the other articles were previously published in Portuguese in other books and Brazilian journals, such as the articles by Luiz Eduardo Soares and Domingos Bernardo Gialluisi da Silva Sá. The compilation also contains original contributions written by researchers dedicated to these topics, such as the texts by Christian Frenopoulo, Sérgio Brissac, Sandra Lucia Goulart, and Labate et al. We hope that this selection will make explicit what the study of the ayahuasca religions has to say on classical and contemporary issues in anthropology. The compilation presents a broad and varied set of ethnographic approaches employed in the initial mapping out of this phenomenon, thus establishing its historical and cultural origins. This book should provide a basis for the development of future work on these religions both in their original contexts and in their expansion throughout Brazil and the world. Their expansion and diversification throughout Brazil and the world may be related to modern projects of religious transit, the construction of national identities by the reappropriation of Indian and popular elements in transnational circuits, migrations and religious diasporas, cultural hybridism, and so on.