Legal scrutiny of school voucher policies initially focused on the establishment clause concerning with allocating public dollars to schools sponsored by religious organizations. In recent years, advocates asserted that the exclusion of faith-based organizations from voucher plans that permit expenditures in secular private organizations violates equal protection and free exercise guarantees. In addition to legal arguments is today's imperative to reform education in ways that promote safe and effective learning environments. Proponents contend that open competition would place healthy pressure on both public and private schools, thus improving outcomes for all children. In contrast, opponents point to the diversion of tax dollars from public schools to support efforts to privatize and abandon the common school just to advance the interests of a small segment of the population. They also view voucher plans as highly divisive in fostering government entanglement with churches and serving as a catalyst for re-segregating public schools. The framework for initial analyses in this article is the evolution of voucher plans, including a historical account of the social unrest that increased demand for public support of privately sponsored schooling through the early 20th century. The perspective shifts from social and economic contexts to state and federal constitutional bases for legal challenges and the reluctance of courts to embrace free exercise and equal protection claims of voucher advocates. Next, there is a description of the legal strategies available to today's voucher rivals in the aftermath of "Zelman v. Simmons-Harris" (2002), which effectively eliminated federal barriers to voucher expansion. The final section describes the parallel course of early school finance lawsuits and our forecast of school voucher litigation in tandem with a discussion of the political struggles around school choice which offer the most promise for influencing judicial outcomes in state courts nationwide. (Contains 79 endnotes and 4 tables.)