Throughout the last decade, cognitive radio systems received a lot of consideration for spectrum optimization and create huge opportunities for interesting research in a wide range of applications. Spectrum access and sharing tasks are widely studied for static nodes; hence, the authors combine, in this paper, multi-agent negotiation for spectrum sharing with user’s mobility. They deploy primary and Cognitive Radio (CR) agents on primary and secondary users, respectively and they define a novel negotiation mechanism in order to allow mobile CR users to access the appropriate spectrum band with negotiated price and duration.