This chapter explores cooperation issues in large‐scale vehicular networks, where vehicles communicate with each other and with the infrastructure via wireless links. High‐level services are built following a cooperative model that depends exclusively on the participation of contributing vehicles. The chapter focuses on the major technical challenges that are currently being resolved from cooperation perspectives for various OSI layers, such as physical and medium access control layers, network and application layers, authentication and security, and so on. It gives an overview on vehicular networks and some existing contributions in the field of cooperative vehicular networks.