Recent research in Software-Defined Networking (SDN) for Vehicular Ad Hoc Networks (VANETs) focuses on enhancing network flexibility, scalability, and centralized control to manage dynamic vehicular environments effectively. SDN introduces a programmable control plane that enables dynamic configuration of routing, resource allocation, and traffic management based on real-time network conditions. Researchers are developing hierarchical and distributed SDN architectures integrated with fog and edge computing to reduce latency and improve decision-making in high-mobility scenarios. Machine learning and artificial intelligence techniques are also being incorporated into SDN controllers for predictive routing, congestion control, and anomaly detection. Additionally, blockchain and security-aware SDN frameworks are being explored to ensure trust, privacy, and robustness in vehicular communication, making SDN a key enabler for intelligent and adaptive vehicular networking systems.