The purpose of this paper is to shed light on the controversial issue of regional development incentives. Although extensive research has been conducted, a review of the literature gives an inconclusive answer to whether economic incentives are effective. Why do researchers arrive at different conclusions, even after analysing the same programmes? Among the problems that we find, for example, is the fact that for some researchers ‘effective’ means the significant location of new firms in targeted areas, while for others the creation of jobs regardless of whether new firms are arriving in a significant fashion. Furthermore, as we elaborate, the selection of an econometric model will have a significant impact on expected results. Different models, with different limitations, will lead researchers to evaluate the same incentive programme but arrive at different conclusions regarding its effectiveness. The contribution of the paper is to inform policymakers about the potential opportunities and pitfalls when designing incentive strategies. This is particularly relevant, given that both the US and Europe have been promoting incentives as a tool for regional economic development.