In 1957, Lee Cronbach called on psychologists to integrate research on cognition and intelligence, and this volume has been dedicated to presenting a progress report of the work in this field. This final chapter will summarize and synthesize the work reported in this volume, and will conclude with an evaluation of our status with respect to Cronbach's call and suggestions for future work in the field.

Research on cognition and intelligence can be characterized as either bottom-up or top-down. Bottom-up approaches focus on identifying the basic information processes, usually measured by elementary cognitive tasks, that underlie individual differences in traditional psychometric tests of cognitive ability. In contrast, top-down approaches study the relationship of intelligence to complex cognitive tasks such as complex problem solving, decision making, and transfer. Each approach brings with it theoretical and methodological strengths and weaknesses, research questions it can and cannot answer. In some ways, these two distinct approaches complement each other, but it is also true that the differences in the research programs' methodologies and assumptions often make it difficult to compare results and synthesize an understanding of the role of cognition in intelligence.

The future of research on cognition and intelligence depends on the willingness of researchers to agree on a set of ground rules and to stretch their comfort zones in terms of their research methods and assumptions.