Post-Traumatic Growth (PTG) refers to the positive psychological changes experienced by individuals following exposure to traumatic events. Despite the proliferation of research, the fragmentation of evidence and the lack of a comprehensive synthesis of existing systematic reviews represent a significant knowledge gap. This umbrella review aims to synthesize evidence from systematic reviews and meta-analyses published between 2020 and 2026 to elucidate the dimensions, predictors, processes, interventions, and research gaps associated with PTG. A systematic search was conducted across PubMed, ProQuest, Scopus, Science Direct, and Google Scholar. Ultimately, 119 eligible articles were analyzed using inductive qualitative content analysis. The findings were organized into ten core themes: (1) conceptualization and the five dimensions of PTG, emphasizing its distinction from resilience and illusory growth; (2) individual characteristics, including resilience, spirituality, and cognitive flexibility; (3) active coping strategies and secure attachment styles as facilitators; (4) environmental contexts such as social support, family, peers, and culture; (5) trauma-related factors, including perceived severity and event type; (6) cognitive processes like intentional rumination, meaning-making, and self-disclosure; (7) theoretical models, temporal dynamics, and neurobiological correlates; (8) growth outcomes regarding psychological well-being, physical health, and existential philosophy; (9) the efficacy of psychological interventions, particularly CBT and mindfulness; and (10) definitional challenges, self-report measurement limitations, and the dearth of longitudinal studies. A “Five-Level Interactional” conceptual model is proposed for empirical testing. Future research should prioritize longitudinal designs with objective indicators, the development of culture-sensitive tools, and the investigation of understudied populations.