—The adoption of wireless vehicular communication technologies would strongly depend on the technologies transmission reliability, required by QoS demanding traffic safety applications, and the system’s scalability as the technology is gradually introduced. To this aim, this work proposes the use of opportunistic transmission policies that dynamically adapt the transmission parameters based on the operating conditions and potential traffic safety risks. The work analyses different configuration proposals with the aim to meeting the strong traffic safety QoS requirements, while maximizing the technology’s robustness and minimising channel congestion, which in turn is crucial to guarantee the future system’s scalability. Keywords; wireless vehicular communication systems, radio resource management, opportunistic and adaptive transmission