In conducting fieldwork among perpetrators of state violence, it is a major methodological problem to gain access to competing factions within the research population. Ethnographers often succeed in finding access to at least one faction but this successful rapport might then immediately close off other factions that mistrust the ethnographer’s politics, intentions, or alleged sympathies. The ethnographic challenge is to find intermediaries or switchboard operators, as they are called in this article, who have established informal channels of communication between hostile factions. Switchboard operators have the following characteristics: discretion, neutrality, lack of formal power, disinterestedness, trustworthiness, and they act as a conduit of communication. This article describes how switchboard operators were located in Argentina, and how they played a crucial role in my fieldwork among a broad spectrum of military perpetrators who had terrorized the Argentine people between 1976 and 1983 with enforced disappearances and state repression.