Ch. 1. The soil microbial biomass: Before, beyond and back / D.S. Powlson -- Ch. 2. Methods for the analysis of soil microbial communities / F. Kunc -- Ch. 3. Vertical distribution of microbial communities in soils / D. Zvyagintsev -- Ch. 4. Use of DNA analysis to determine the diversity of microbial communities / V. Torsvik, J. Goksoyr, F.L. Daae, R. Sorheim, J. Michalsen and K. Salte -- Ch. 5. A new approach to direct extraction of microorganisms from soil / N.C. Smith and D.P. Stribley -- Ch. 6. Analysis of microbial communities by flow cytometry and molecular probes: Identification, culturability and viability / C. Edwards, J. Diaper, J. Porter, D. Deere and R. Pickup -- Ch. 7. Physiological analysis of microbial communities in soil: Applications and limitations / T.-H. Anderson -- Ch. 8. A community-level physiological approach for studying microbial communities / J.L. Garland and A.L. Mills.