1. Role of economics in crop genetic diversity / E. Meng, J.P. Brennan, and M. Smale -- 2. Conceptual framework for crop diversity concepts and measurement / E. Meng, M. Smale, and J.P. Brennan -- 3. Agricultural policy, the wheat economy, and crop diversity in China / J. Huang and S. Rozelle -- 4. Policy influences on wheat genetic diversity in Australia / D. Godden and J.P. Brennan -- 5. Breeder demand for and utilization of wheat genetic resources in Australia / J.P. Brennan ... [et al.] -- 6. Wheat diversity changes in China, 1982-97 / R. Hu and E. Meng -- 7. Wheat diversity changes in Australia, 1965-97 / J.P. Brennan, A.B. Bialowas, and D. Godden -- 8. Explaining spatial diversity in wheat in Australia and China / M. Smale ... [et al.] -- 9. Determinants of wheat diversity in Chinese household farms / P. Qin ... [et al.] -- 10. Wheat diversity and total factor productivity in China / S. Jin ... [et al.] -- 11. Cost function analysis of wheat diversity in China / E. Meng ... [et al.] -- 12. Overview and policy implications / E. Meng and J.P. Brennan.