This task is particularly urgent as the greatest population growth will be in cities in developing countries where significant urban transport challenges already exist (see section 3.3.1 below). Such challenges are particularly pronounced in developing countries where strong migration to urban areas and increased private motorization fuelled by strong economic growth, are outpacing infrastructure development and the expansion and modernization of public transport systems. The process of achieving more sustainable urban transportation systems, designed with the principle of accessibility at their core, depends on the participation of all stakeholders in cities: the authorities, the private sector and the citizens, within the principles of democracy. A successful process will depend on effective governance of land use and transportation, where new housing and commercial planning will entail simultaneous transportation systems design, careful neighbourhood design, strategic infrastructure investments, and fair, efficient and stable funding (Kennedy et al.,