This research addresses the influence of mandate design upon implementation efforts and regulatory styles. Empirical analyses of these relationships are conducted for state-level land-use and development-management mandates enacted by California, Florida, North Carolina, Texas, and Washington. Three key findings provide insights about the role of mandate design in facilitating policy implementation. First, implementation efforts are more easily influenced than regulatory styles. Second, it is more difficult to foster conciliatory regulatory styles than it is to foster more legalistic styles. Third, a high degree of statutory coherence is not a necessary condition for strong implementation efforts. More generally, the findings show that policy designers can enhance implementation efforts and shape regulatory styles by altering key mandate features.