The Cost-Benefit Analysis (CBA) is characterized by the fact that alongside financial returns, it simultaneously seeks to assess the most significant quantitative and qualitative aspects of the economic-social impact and to attribute monetary value to such aspects. To attribute monetary value to cost-benefit analysis, various methods, such as willingness-to-pay, WTP or long-run marginal cost (LRMC), are applied.
The European Commission's guideline provides the following cost-benefit analysis definition: it is a conceptual methodology used for systematic quantitative evaluation of a public or private project to determine if and what value the project has from a social perspective. Cost-benefit analysis differs from the simple financial evaluation in that it takes into account all the benefits and losses (costs) incurred by social agents. Cost-benefit analysis generally uses accounting prices (i.e., alternative costs for goods, which sometimes are different from actual market prices or regulated rates).
The EC CBA guidelines emphasize that cost-benefit analysis works as an appropriate method in making competent decisions. By using the cost-benefit analysis method, a project's contribution to the welfare of a region or a country can be measured as well as the contribution of an investment project to theobjectives of the EU Cohesion Policy can be assessed
The social and economic impacts of investments are valued by economic analysis, which is carried out from the perspective of the whole society. EK CBA guidelines suggest a general equilibrium methodology and distinguish five steps in economic analysis: conversion of market prices to accounting prices, non-market type monetary impact, the inclusion of additional indirect effects (if any) in the assessment, estimated cost and benefit discounting, calculation of economic performance indicators