The six articles of this issue discuss the place of meta-analysis in the health professions and present two state-of-the-art meta-analyses using a variety of innovative methodologies, statistics, and secondary analytic procedures. A survey conducted for this issue and its sequel explores interventions to facilitate meta-analysis. (SLD)

Two chapters of this issue consider critical multiplism as a research strategy with links to meta analysis and generalizability theory. The unifying perspective it can provide for quantitative and qualitative evaluation is discussed. The third chapter explores meta analysis as a way to improve causal inferences in nonexperimental data. (SLD)

The eight chapters of this theme issue evaluate a large-scale intervention, the New York City Public Schools Integrated Learning Systems Project. The overall evaluation contains ethnographic studies of project schools, statistical investigations of outcomes in terms of student achievement and attitude, comparisons of system costs to other systems,…