Previous scholarship on the political thought of the American founding has concluded that the founders amalgamated liberalism and republicanism but has not yet identified the precise contours of this combination. The first section of this article lays out the debate between liberalism and republicanism. The second section reveals that the founders, far from promoting laissez-faire, supported and enacted a wide array of regulations at the local, state, and national levels. The third and fourth sections discuss the justification for regulation and demonstrate that the founders' approach to liberalism harmonized the exercise of individual rights and the common good, foundations that have been considered exclusively liberal and republican, respectively. The article concludes by suggesting that regulation provokes questions for the liberal/republican categories, since neither approach adequately explains the founders' rationale in favor of both liberalism and regulation.