and demand management to mitigate congestion and environmental impacts. The policies were popularised in a 1963 government publication, Traffic in Towns. The contemporary Smeed Report on congestion pricing was initially promoted to manage demand but was deemed politically unacceptable. In more recent times, the approach has been caricatured as "predict and provide" to predict future transport demand and provide the network for it, usually by building more roads. The publication of Planning Policy Guidance 13 in 1994 (revised in 2001), followed by A New Deal for Transport in 1998 and the white paper Transport Ten Year Plan 2000 again indicated an acceptance that unrestrained growth in road traffic was neither desirable nor feasible. The worries were threefold: concerns about congestion, concerns about the effect of road traffic on the environment (both natural and built) and concerns that an emphasis on road transport discriminates against vulnerable groups in society such as the poor, the elderly and the disabled. These documents reiterated the emphasis on integration: integration within and between different modes of transport integration with the environment integration with land use planning integration with policies for education, health and wealth creation. This attempt to reverse decades of underinvestment in the transport system has resulted in a severe shortage of transport planners. It was estimated in 2003 that 2,000 new planners would be required by 2010 to avoid jeopardising the success of the Transport Ten Year Plan . In 2006, the Transport Planning Society defined the key purpose of transport planning as: to plan, design, deliver, manage and review transport, balancing the needs of society, the economy and the environment. The following key roles must be performed by transport planners: take account of the social, economic and environmental context of their work understand the legal, regulatory policy and resource framework within which they work understand and create transport policies, strategies and plans that contribute to meeting social, economic and environmental needs design the necessary transport projects, systems and services understand the commercial aspects of operating transport systems and services know about and apply the relevant tools and techniques must be competent in all aspects of management, in particular communications, personal skills and project management. The UK Treasury recognises and has published guidance on the systematic tendency for project appraisers to be overly optimistic in their initial estimates. United States Transportation planning in the United States is in the midst of a shift