Part I: Approaches to Defining, Monitoring, Evaluating and Managing Soil Quality 1: Introduction, A Benedetti and O Dilly 2: Defining Soil Quality, R G Burns, P Nannipieri, A Benedetti and D W Hopkins 3: Monitoring and Evaluating Soil Quality, J Bloem, A J Schouten, S J Sørensen, M Rutgers, A van der Werf and A M Breure 4: Managing Soil Quality, M Schloter, J C Munch and F Tittarelli 5: Conclusive Remarks, A Benedetti, P C Brookes and J M Lynch Part II: Selected Methods 6: Microbial Biomass and Numbers 7: Estimating soil microbial biomass, A Fließbach and F Widmer 8: Microbial biomass measurements by fumigation-extraction, P Brookes and R G Joergensen 9: Substrate-induced respiration, H Höper 10: Enumeration and Biovolume Determination of Microbial Cells, M Bölter, J Bloem, K Meiners and R Möller 11: Soil Microbial Activity 12: Estimating soil microbial activity , O Dilly 13: Soil respiration, M Pell, J Stenström and U Granhall 14: Soil nitrogen mineralization, S Canali and A Benedetti 15: Nitrification in soil, A Bollmann 16: Thymidine and leucine incorporation to assess bacterial growth rate, J Bloem and P R Bolhuis 17: N2O emissions and denitrification from soil, U Sehy, M Schloter, H Bothe and J C Munch 18: Enzyme activity profiles and soil quality, L J Shaw and R G Burns 19: Soil Microbial Diversity and Community Composition 20: Estimating soil microbial diversity and community composition, J D van Elsas and M Rutgers 21: Soil microbial community fingerprinting based on total community DNA or RNA, J D van Elsas, E M Top and K Smalla 22: Phospholipid fatty acid (PLFA) analyses, A Palojärvi 23: Substrate utilisation in Biolog plates for analysis of CLPP, M Rutgers, A M Breure and H Insam 24: Plant-microbe Interactions and Soil Quality 25: Microbial ecology of the rhizosphere, P Lemanceau, P Offre, C Mougel, E Gamalero, Y Dessaux, Y Moënne-Loccoz and G Berta 26: Nodulating symbiotic bacteria and soil quality, A Hartmann, S Mazurier, D N Rodríguez-Navarro, F Temprano Vera, J-C Cleyet-Marel, Y Prin, A Galiana, M Fernández-López, N Toro and Y Moënne-Loccoz 27: Contribution of arbuscular mycorrhiza to soil quality and terrestrial ecotoxicology, S Gianinazzi, E Plumey-Jacquot, V Gianinazzi-Pearson and C Leyval 28: Concepts and methods to assess the phytosanitary quality of soils, C Alabouvette, J Raaijmakers, W de Boer, R Notz, G Défago, C Steinberg and P Lemanceau 29: Free-living plant-beneficial microorganisms and soil quality, Y Moënne-Loccoz, S L Woo, Y Okon, R Bally, M Lorito, P Lemanceau and A Hartman 30: Census of Microbiological Methods for Soil Quality, O Dilly