A traditional handbook on transport economics teaches policy-makers and students that infrastructure policy consists of two components, i.e., infrastructure investment and charging users for infrastructure costs. The latter is part of the levy imposed on the transport users for the marginal external cost that they cause. An even important issue is how authorities should approach decision-making on investments in transport infrastructure.

It all starts with a correct definition of transport infrastructure investments. It not only concerns investment in new infrastructure but also improvement works, repairs, and maintenance. Just have a look at the national accounts to see how huge amounts of money are involved. From a scientific point of view, the economic decisions about transport infrastructure expenditures must always be analyzed in the same way: the investment should only be made as long as the benefits outweigh the costs.

传统的运输经济学手册教导决策者和学生，基础设施政策包括两个部分，即基础设施投资和向用户收取基础设施费用。后者是对运输用户征收的税款的一部分，因为他们造成了边际外部成本。一个更重要的问题是，当局应如何处理交通基础设施投资的决策。

这一切都始于对交通基础设施投资的正确定义。它不仅涉及对新基础设施的投资，还涉及改善工程、维修和维护。只要看一下国民账户，看看其中涉及到的巨额资金。从科学的角度来看，有关交通基础设施支出的经济决策必须以同样的方式进行分析：只有在收益大于成本的情况下，才能进行投资。