Mercedes Perez Matus and Hugo Vaccaro Kosovich were dis-tinguished doctors and microbiologists from the ordinary chair of Bacteriology at the Faculty of Medicine of the University of Chile. In 1931, both doctors were hired by the Faculty of Medicine to reorganize the convulsed Chair of Bacteriology after the political crisis of 1931. In the same period, the prominent Pasteur Institute researcher Eugène Wollman came to Chile to direct the Sanitas Institute (1929-1931), incorporating in our country the knowledge about bacteriophages and the techniques for their isolation. The long teaching and research work of Vaccaro and Pérez spanned almost 40 years (1931-1970). They published numerous scientific articles, being one of their favo-rite topics, in the early years, the study of bacteriophages that they learned together with Wollman. In the 1940s, under the leadership of Drs. Vaccaro and Pérez, phage therapy began in Chile.