This study examines the mediating role of the satisfaction of basic psychological needs (need for relatedness, need for competence, need for autonomy), as derived from self-determination theory, between college teachers' relational trust in three main referents (the administration, colleagues, and students) and their optimal functioning (vigor, affective organizational commitment, job performance). The study was conducted among 422 teachers from French-language colleges in the province of Quebec (Canada). The results obtained using structural equations provide support for the proposed model, while identifying specific ways in which trust in the different referents is connected to the satisfaction of psychological needs, as well as to the studied indicators of functioning. Theoretical and practical implications, as well as directions for future research are discussed.