Evaluation of regional public infrastructure projects is needed to ensure the effective and efficient use of scarce taxpayer funds. There are several methods used to evaluate public infrastructure projects, including cost benefit analysis (CBA) and economic impact analysis (EIA). CBA is widely used by governments to estimate the real social value of a project. However, CBA does not necessarily account for regional impacts such as the effects on employment and growth and, thus, may not be adequate to properly measure regional impacts against related government policy objectives. Governments can use EIA to capture these impacts as an adjunct to CBA. This paper reviews the pros and cons of both CBA and EIA and presents an empirical analysis of both appraisal approaches. Both approaches are applied to a case study of the proposed South West Illawarra Rail Link (SWIRL), which is a $1.6 billion infrastructure project designed to improve the railway connectivity between Greater Sydney and the Illawarra region.