In this article, we study the impact of a French enterprise zone program-the 'Zones Franches Urbaines' (ZFUs) policy-on establishment location decisions and on labor market outcomes. Our main identification strategy, which combines spatial and time differencing, shows that conditional on locating in a municipality that hosts a ZFU, the policy has a positive and sizable impact on the probability to locate in the ZFU part rather than in the non-ZFU part of municipalities. However, the impact is highly heterogeneous across zones, industries and firms. We also show that this positive effect is entirely due to within-municipality diversion effects. Regarding labor market outcomes, the policy has a positive effect on employment, especially for low-wage workers. As for wages, the effect is null for low-wage workers, and negative for high-wage ones.