There's an EU consensus on the need to introduce and reinforce the principle and the practice of cost-based transport charges. Pricing of transport infrastructure use has been identified, since the Green Paper of 1995 on fair and efficient pricing, as a pillar of the strategy towards a more sustainable transport system. Much has since then happened over a relatively short period and visible progress has been made both in the scientific area and in the policy making realm. On the policy making side, the Green Paper has been followed by the White Paper of 1998 on the fair payment for infrastructure use and the White Paper of 2001 on the European transport policy till 2010. Pricing reforms are still hindered by the existence of specific, critical gaps in the available body of knowledge, and by the insufficient level of consensus currently achieved within the transport community of stakeholders. Furthermore, the state of advancement of research and policy making on the issue of a more fair and efficient pricing system is uneven between modes; this implies that a differentiated approach has to be taken for rail/road and air/maritime. The main objective of the Imprint-Net project was to provide a discussion platform for policy makers, transport operators, researchers and other stakeholders to exchange views on the implementation of new pricing regimes, cost calculation methods, derivation of tariffs to be levied and on successful approaches to overcome barriers and to affect attitudes and perceptions. Imprint-Net directly benefited from the experience accrued by its predecessors CAPRI (1998-1999) and Imprint-Europe (2001-2004), while featuring major innovations, in both contents and organisation. It cooperated closely with all relevant pricing research projects. As for its predecessor, the basic thrust of the Imprint-Net is to improve and enhance the links between pricing RTD and the policy community, notably by: - transferring research findings to policy makers and stakeholders involved in the formulation and implementation of transport pricing reforms; - stimulating the debate among stakeholders in order to build consensus on the principles and the practice of transport pricing, thus facilitating and accelerating the implementation of pricing reforms and contributing to the implementation of the EU transport policy. Particular emphasis is laid on the following priorities: - air and waterborne modes, for which the knowledge is less advanced; - links between infrastructure charging and investment needs; - pricing reforms in NAS, in the perspective of EU enlargement. The main result of the project has been the achievement of consensus among stakeholders on recommendations about how to implement pricing reforms in the transport sector. The project impact analysis of pricing policies has highlighted the need for additional research and further evidence gathering, in particular for the transport modes (waterborne) for which the implementation of pricing reforms lags behind. In the rail sector the market structure seems to play a fundamental role: the higher the level of competition between private operators (particularly in the freight sector), the more pricing reforms are deemed to provide the expected results in terms of modifying users' behaviour. As far as the road sector is concerned, pricing in itself does not appear to ensure a significant modal shift towards more sustainable modes. In the interurban road sector there is evidences that a traditional allocation of road maintenance and renewal costs based on standard axle kilometres in the most congested areas appears reasonable to start with. There is good evidence that technology is improving over time, whilst successive implementations help to increase acceptability. Some form of independent regulation of charges and use of revenues may also aid acceptability. It may be simpler and more necessary to charge larger vehicles such as heavy goods vehicles rather than passenger cars to begin with. This leads to a need for a kilometer-based charge varying with the characteristics of the vehicle (gross weight and axle load) for heavy goods vehicles, buses and coaches. Relatively simple technology can implement such a charge, with varying levels between countries. In the rail sector the starting point for rail infrastructure charges should be a charge per gross tonne km to reflect marginal wear and tear costs. In the absence of specific evidence for the country concerned, this might be approximated as 30 % of average track maintenance and renewals cost. Where there is a wide variety of types of rolling stock in terms of axle weights, speed and unsprung mass, engineering formulae may be used to weight the different types of rolling stock according to the equivalent damage per gross tonne kilometre they do. Where data exists, it may also make sense to segment charges according to the type of track (e.g. high speed, other main lines, secondary lines, low density lines), as there is evidence that marginal costs are lower the higher the quality of the track. In the maritime sector it needs to be examined if there is a net benefit from the implementation of social marginal cost pricing (SMCP). We need to watch out for a tunnel vision regarding SMCP, a cost-benefit analysis is needed, together with a regional impact analysis and a socio economic impact analysis in order to establish correctly whether the introduction of pricing is needed. The probable impact will be increased transport costs for the end user. In the case of road transport different outcomes of the CBA were predicted in the case of the Stockholm, from net benefits to losses to society. It is not the question of the perfect SMCP scheme but what is a good scheme of pricing. Road pricing has in general the goal to reduce congestion, this is different from maritime transport. In the waterways transport sector, the expert group agrees with internalisation of external costs, the condition is that implementation in all modes is necessary (level playing field), we are looking forward to implementation. Transparency and easy implementation of the system (introduction of pricing regimes for other modes at the same time) is the main focus to get the pricing scheme accepted by the users of the system. The group is not sure about possible lobbying from e.g. the railway lobby (especially in central Europe) or the road sector (especially in Western Europe). Therefore the inland waterway (IWW) sector needs to be proactive to arrange the introduction of pricing. In the air sector there is the need to improve the evaluation and the impact assessment of the external costs of air transport; with particular reference to global warming, noise, congestion and scarcity. To reach a common agreement on methods and order of magnitude of the monetary evaluation of the external costs of air transport (both "en route" and at airport level) represents an important precondition for carrying out pricing reforms.