Wireless vehicular communications is a cutting edge set of technologies driven by the vision of providing a suite of original applications, and supported by emerging standards such as IEEE 802.11p. In turn the popularity of these applications is one of the key factors, which will drive the uptake of these vehicular communications technologies and ultimately determine their market success. Applications for vehicular communications can be placed in three main categories - Traffic Safety, Traffic Efficiency and Value-added Services (e.g. Infotainment/Business). Our work focuses on the provision of traffic efficiency services as we believe they offer an immediate benefit and can be adopted quickly by a large number of potential users. Satellite navigation systems provide a ready made deployment platform for these types of services and have already proven popular (14.4 million portable satellite navigation systems sold in Western Europe in 2007). There is also an existing trend toward complementing satellite navigation-related technology with local area wireless communications (by 2013 34% of all portable navigation devices will feature wireless cards 2). Our emphasis is on an infrastructure-based approach as this allows early adopters of wireless enabled satellite navigation devices to receive useful services from day one, regardless of the penetration level of the technology. This thesis describes Smart City, a novel framework, which purposes the use of wireless communication to make city life greener and more efficient. A major contribution to this framework is the proposed intelligent traffic management module. A route management service, which is powered by a best route selection algorithm, is put forward as a prototypical traffic efficiency service for this module. The novel aspect is that the algorithm minimizes journey times and traffic congestion as well as fuel consumption and emissions. Testing has shown how the algorithm provides-shorter journey times, a reduction in fuel consumption and harmful emissions and also results in financial savings. We have proposed and implemented an infrastructure-based communication scheme that enables prioritization of services provided to vehicles.