"Sanapan " is the unfinished and unpublished manuscript of the artist, photographer and explorer Guido Boggiani (1861-1902), killed in dramatic circumstances by the Chamacoco Bravo Indians of the South American Gran Chaco. The manuscript was found a century later among the papers deposited by Alfred M traux at Yale University. Intended for publication, the manuscript, written during practically the last fifteen years of his South American life, focuses on the Sanapan , an indigenous people that Boggiani considered representative of the group he called "Machicu " today known as "Lengua-maskoi" or "enlhet-enenlhet." This first published bilingual version of Sanapan is complemented by five appendices and four contextual essays. The first of the appendices corresponds to chapter IV --"Guana del Chaco"-- of Boggiani's "Compendio de Etnograf a Paraguaya moderna" --his more important ethnographic work. It appeared, in Spanish, in Asuncion del Paraguay in 1901. Never translated, it is considered to be the author's mature statement of his overarching ethnographic research plans in the Gran Chaco. Other appendices consist of supplementary records of documentary materials found with the manuscript. The contextual essays are offered to facilitate the understanding and analysis of Boggiani's text. In the foreword, Jos Braunstein, explains the ethnographical aspects of the book; Maruska Kokrhanek, the late anthropologist from the University La Sapienza of Rome, outlines the life and work of the author; Zelda Franceschi, of the University of Bologna, examines the characteristics of Boggiani's writing style; in the closing essay, Edgardo C. Krebs, of the Smithsonian Institution, explores the meaning of Boggiani's artistic and scientific work for the history of anthropology.