Pre-print, Working paper: Since 1996 the French rural development policy has defined Rural Revitalization Zones (ZRR) in which the enterprises of less than 50 employees are eligible for tax exemptions. The fiscal exemptions are of great scale in the ZRR (30% of gross salary for the wages below 1.5 minimum wage) and they potentially apply to 10.7% of below 50 employees enterprises. Until now, the impact of the device on the economy has only be analysed in descriptive studies. In this paper, a measure of the causal impact of the exemptions in ZRR is suggested. A feature in the implementation of the device allows to use a well known econometric method in the evaluation of public policies. The enterprises located in the ZRR are the only one which can benefit from the exemptions. Moreover these zones have been defined using precise population density and demographics criteria. A Regression Discontinuity Design is therefore well suited to the evaluation the policy. It allows disentangling the impact of the ZRR implementation on firm and jobs creation from the background characteristics in the ZRR. Our results show that the tax exemptions neither have any significant impact on employment nor on firms creation in disadvantaged rural zones.