1. Editorial

   • Piet Lens

   Editorial Introduction Pages: 1 - 2

2. Key roles of pH and calcium metabolism in microbial carbonate precipitation

   • Frederik Hammes
   • Willy Verstraete*

   OriginalPaper Pages: 3 - 7

3. Challenges and opportunities in the use of iron in water and wastewater treatment

   • T.D. Waite

   ReviewPaper Pages: 9 - 15

4. A review of non-DLVO interactions in environmental colloidal systems

   • D. Grasso*
   • K. Subramaniam
   • J. Bergendahl

   ReviewPaper Pages: 17 - 38

5. Contribution of molecular microbiology to the study in water pollution removal of microbial community dynamics

   • Patrick Dabert
   • Jean-Philippe Delgenès
   • Jean-Jacques Godon

   ReviewPaper Pages: 39 - 49

6. Improved nitrogen removal by application of new nitrogen-cycle bacteria

   • Mike S.M. Jetten
   • Markus Schmid
   • J. Gijs Kuenen

   ReviewPaper Pages: 51 - 63

7. Trends in application of gas-phase bioreactors

   • Edward D. Schroeder

   ReviewPaper Pages: 65 - 74

8. New developments in treatment of heavy metal contaminated soils

   • L. Diels
   • N. van der Lelie
   • L. Bastiaens

   ReviewPaper Pages: 75 - 82

9. Integrating process engineering and microbiology tools to advance activated sludge wastewater treatment research and development

   • Jürg Keller
   • Zhiguo Yuan
   • Linda L. Blackall*

   ReviewPaper Pages: 83 - 97

10. Instructions for Authors

    Instructions for Authors Pages: 99 - 102