1) The document summarizes Bechara Choucair's presentation on using evidence to combat childhood obesity from the perspective of a health commissioner in Chicago. 2) It provides data on childhood obesity rates in Chicago schools ranging from 12.7% to 32.9% depending on the neighborhood and highlights three of Chicago's initiatives to address this issue: school-based interventions, intergovernmental collaboration, and multi-sector community development efforts. 3) Examples of interventions discussed include revising school wellness policies, improving access to healthy foods, and expanding programs for breastfeeding and daycare standards.