Presentation by Alex Molnar at the Frontiers Meeting of the Wellcome Trust, on "Environmental and Behavioural Determinants of Child Obesity" (May 29, 2009, Cambridge, England). Molnar discussed marketing of foods to children in schools in the context of obesity prevention. His remarks centered on the reasons food marketers are interested in schools, the forms that food marketing takes in schools, the products that are heavily marketed in schools, and policy options.