Background: Between roughly 18 and 29 years of age, a person consolidates the self-identity that will organize much of adult life, and university students pass through this window under compounded academic, social, and vocational pressures. Emotional tolerance—the capacity to remain in contact with negative affect while continuing to act toward one's goals—has been repeatedly implicated in how deeply identity exploration proceeds. Although intervention research drawing on this link has accumulated for over a decade, it remains dispersed across therapeutic traditions and has never been integrated around the identity question itself. Methods: This review synthesizes theoretical and empirical literature on emotional tolerance and self-identity in college populations. Studies were organized into five intervention families according to their theoretical lineage: dialectical behavior therapy (DBT) skills training, narrative and identity-focused programs, emotion regulation training, mindfulness and acceptance and commitment therapy (ACT) approaches, and creative expression interventions. Each family was appraised with respect to its theoretical grounding, the strength and consistency of its evidence, and its plausible mechanisms of change; the methodological quality of the evidence base was then assessed as a whole. Results: DBT-informed programs showed the most consistent effects, with 15 of 16 reviewed studies reporting gains in emotion regulation, distress tolerance, or mindfulness that extended beyond symptom relief. Identity-focused and narrative programs reduced identity confusion and increased identity integration among emerging adults; emotion efficacy training improved distress tolerance while lowering regulation difficulties and experiential avoidance; seven of nine campus mindfulness programs improved emotional distress or self-perception; and ACT-based and creative expression approaches returned promising but preliminary findings. Mechanistically, emotional tolerance appears to buy the psychological time that sustained exploration requires, while a consolidated identity in turn stabilizes emotional responding, forming a reciprocal loop on which current interventions operate. Conclusions: Targeting emotional tolerance constitutes a theoretically coherent and empirically supported route to promoting self-identity development in college students. Confidence in this conclusion is tempered by the scarcity of longitudinal follow-up, heterogeneous outcome measurement, reliance on Western undergraduate samples, and thin reporting of implementation fidelity. Future work should emphasize extended follow-up designs, standardized identity-relevant outcomes, cross-cultural validation, and implementation research under realistic campus conditions.