This case study explores the way interactions between study participants, the researcher, and the research assistant affect trust-building and the engagement of study participants. The researcher’s reflexive account draws upon the author’s 8-month period of fieldwork on alcohol use in the Peruvian Andean highlands where mistrust had become used as a survival strategy during the civil conflict. Using the concept of “triple subjectivities,” this reflexive analysis presents the shifting nature of a relational process within which a range of positioning factors associated with the researcher and assistant––which took on unexpected meanings in the socio-cultural and historical context of the study––influenced trust-building, physical and interpersonal access to study participants, and knowledge construction with the participants. In global mental health research, researchers encounter and negotiate the differences, connections, and tensions that shape and are shaped in the power imbalance that is embedded in the dynamics of the researcher–research assistant–participant relationship. Iterative revisiting of the relational practices unique to this relationship may contribute to constructing knowledge that is more responsive to local contexts and needs.