The topic of this first MicroSoil meeting in Saint Loup, following two earlier ones in Dundee (Scotland) organized by Wilfred Otten, was “Elucidating microbial processes in soils and sediments: Microscale measurements and modeling”. As with earlier MicroSoil workshops, the focus was on the microscale description of soil processes. Significant progress had been achieved in this field over the previous years, and a gathering of some of the specialists seemed indicated, to take stock of advances made and to plan future research. The audience consisted of 49 researchers, from 10 different countries.