The 1973 Supreme Court decision in Wisconsin v. Yoder reenforced and amplified the Court's earlier holding in Sherbert v. Verner that the free exercise clause of the first amendment requires the state to render substantial deference to religiously motivated behavior in the application of its laws and regulatory schemes. In this article, Mr. Marcus traces the evolving standards of free exercise doctrine and observes that the "balancing test" which has resulted from that evolution requires still further refinement to give religious freedom its full constitutional due. The author then illustrates how the new standards of free exercise might be applied in a variety of situations in which free exercise claims are most commonly asserted.