My research filosophy: Current research on microbial ecology generally focuses on the microorganisms that are directly involved in a particular process (e.g. benzene degradation, ammonium oxidation). However, these microorganisms form part of an ecosystem consisting of interacting organisms. Biological processes cannot be understood by studying just the individual components, as has become clear from the application of Metabolic Control Analysis (MCA) to biochemical pathways (see other research activities in our department). Therefore, I focus on the ecosystem as a whole and also assess other functional groups that indirectly influence a particular process. I use theory and experimentation iteratively to understand how interactions between microorganisms give rise to ecosystem function.