When the concept of charter schools was first implemented in California in 1993, the goal was to allow the modification of existing public schools or the creation of wholly new ones that would be less rule-bound than traditional public schools but more accountable for student achievement. For some charter advocates, simply providing such alternatives that satisfy parents and students is enough to justify having charter schools. The large majority of supporters, however, see other potential benefits for education quality in general. Schools will compete for students and the funding that goes with them, the thinking goes, thereby motivating schools to improve and tailor their programs to meet students' needs just as competition in the marketplace can spur innovation, efficiency, and better service among private firms. Charter schools that cannot compete will close like unsuccessful business ventures do, they say. Or those that do not abide by the terms of their charter will have it revoked by their chartering agency. In contrast, they say, charters that succeed can serve as models for other public schools--charters and noncharters. This report not only compares charters to noncharters, but also breaks charters down into types to unmask variations within the overall pattern. (Contains 14 figures.) [This report was written with support from Noli Brazil, Susan Frey, and Ron Zimmer.]