We have read the commentaries with great interest. They vary greatly regarding the possibility of achieving a general model for separatist conflict solution, and there are certainly both practical problems as well as difficult priorities of principles. Several issues are addressed by more than one commentator, so we chose a discussion by issue rather than by commentator.

In vitro fertilization (IVF) and other assisted reproduction technologies (ARTs) have become widely accepted as therapy for a wide array of fertility problems and accompanied by the rapid expansion of clinics that provide a full range of ARTs. Although these technologies undoubtedly offer benefits for some individuals, they raise important questions over reproductive rights to safe and effective treatment as well as access. This article analyzes current data concerning the safety, effectiveness, and cost of IVF. It concludes that IVF and related techniques have been transformed too rapidly and easily from experimental to therapy status, despite evidence that suggests considerable caution is warranted. Unfortunately, the widespread diffusion of IVF has preceded rather than followed firm evidence of its value in extending the reproductive rights of women and couples. Resources might better be directed toward prevention of fertility problems and discovering the causes of infertility.

Douglass North, in his seminal work Institutions, Institutional Change, and Economic Performance, defined institutions as “the humanly devised constraints that shape human interaction,” existing within a hierarchical continuum ranging—in order of increasing formality—from taboos, customs, and traditions to more formal constraints such as individual contracts, specific bylaws, common laws, statutes, and constitutions. According to North, institutions evolve as piecemeal economic reactions to the high transaction costs attending greater social complexity. This article tests North's theory against an evolving system of humanly devised constraints: society's mechanism for reimbursing physicians. After examining eight reimbursement systems that range from primitive to complicated—(1) Zinacantan, Mexico, (2) Confucian China, (3) ancient Rome, (4) colonial America and seventeenth-century Britain, (5) the “guild free choice” model, (6) private third-party insurance, (7) government insurance, and (8) HMOs and managed care—I conclude that a “top-downward” model provides a better explanation of physician reimbursement constraints than does North's “bottom-upward” model.

Bryan Vila's general paradigm for understanding criminal behavior focuses on the role of developmental factors in determining motivation for crime (1994:338). In his recent proposal in PLS, Vila states that criminality is “a predisposition that disproportionately favors criminal behavior” (1997:4). He suggests, further, that