This address provides a historical perspective on the concept of school effectivenss and argues for an enlightened synthesis of normative and empirical values. The first part, "Early Images of Effective Schooling," reviews the evolution of discourse on school effectiveness since the turn of the century. Although the early discussions were unscientific by modern standards, these educators had a clearer conception than their modern counterparts of the values, or basic philosophical presuppositions, underlying their view of education. A distinction is drawn between this normative view and the more modern empirical view, which defines good schools by measurable outcomes. The second part, "Three Nightmares about Education," discusses stereotyped fears among educators: policymakers' fear of inept teachers resisting implementation of research-based policy; teachers' fear of bureaucratic interference with their professional autonomy; and researchers' fear that their findings are either neglected or overgeneralized in practice. The third part, "Making Your School More Effective," suggests that the conditions for making average schools excellent may be fundamentally different from those for making poor schools marginally effective. Effectiveness can be measured empirically; excellence depends on normative standards. The final section, "A Radical Criterion for Effective Schools," suggests that effective schools are places that are educative for teachers as well as for students. (TE)