Solvent vapor annealing (SVA) reshapes thin organic films, guiding phase separation and crystallinity. By adjusting vapor exposure, researchers tune nanoscale morphology, optimize charge transport, and improve stability in organic electronics. This evergreen overview surveys mechanisms, characterization approaches, and practical implications for solar cells and transistors, emphasizing linkages between solvent choice, annealing conditions, and long-term device performance in real devices and scalable processes.