Cognitive Radio (CR) is an important technology for the evolution of wireless communications worldwide. Cognitive radio enables the verification of the electromagnetic spectrum availability. Consequently, it permits the modification of the transmission parameters through the interaction with the environment. By monitoring the available frequency band, cognitive users can opportunistically occupy spectral bands with no harming or interference to other users or applications. Cognitive vehicular networks represent a new tendency in the automotive market. New and future models are being released with pre-installed reconfigurable devices; software defined radio (SDR) offers new possibilities for the transmission of intra-vehicular commands as well as dynamic access to Wi-Fi and other wireless services while the car is in movement. In this context, this paper aims to describe the cognitive radio technology and its potential applications and perspectives in the automotive market.