This paper studies the effects of Job Creation Tax Credits (JCTCs) enacted by U.S. states over the past 20 years. First, we investigate whether JCTCs stimulate within-state job growth. Second, we assess from where any increased employment comes from ? in-state or out-of-state? Third, we evaluate when JCTCs' effects occur. In particular, we test for negative anticipation effects between JCTC enactment and when legislation goes into effect. We investigate these questions using a difference-in-differences estimator applied to monthly panel data on employment, the JCTC value, the JCTC effective ...