The EIB performs economic appraisals of the projects it considers for investment. Thereby, it ensures that projects add sufficient value to society to merit support. Beyond considerations of financial profitability to investors, the economic appraisal also addresses the wider value generated by the project to society. This comprises benefits and costs to project final users, the taxpayer and third parties, allowing for all applicable market failures, such as environmental externalities. Since the publication of the first edition of this document in 2013, the EIB has been transformed into the EU Climate Bank. The way it values carbon emissions has been updated, as have various other elements of economic appraisal, in keeping with developments in the specialist literature, policy and practice. This second edition of the document gives the reader an updated view of how economic appraisal is currently conducted at the Bank. It also mentions the areas on which the EIB is currently working to ensure that it is at the forefront of economic appraisal practice.