Statistics show that the number of casualties due to traffic accidents exceeds one million each year. For the development of systems that prevent vehicle collisions, vehicular communication is considered a promising technology. This paper focuses on design aspects of communication systems that support the development of collaborative active safety systems such as collision warning and collision avoidance. We introduce a design method for safety communication systems that includes a set of analyses and a reasoning system for modeling and analyzing traffic scenarios. An overview of a specific solution for communication is presented in this paper. This solution proposes techniques for network organization and data dissemination that make use of contextual information. This allows the development of a communication system that is adaptable to the specifics of the traffic situation.