Authoritative and comprehensive reviews of studies on the nature and extent of food marketing to children indicate that children are exposed to high levels of food marketing and that the 'marketed diet' typically comprises energy-dense, micronutirent-poor foods. However, the implication of causality between marketing, product exposures and childhood obesity is not universally accepted. A vigorous discussion rages about appropriate policy responses to children's exposure to food marketing. The advocacy by many health and consumer groups for tighter government restrictions on food marketing is juxtaposed to the views held by many in the food and advertising industries. Pivotal in this debate is the role of evidence in policy decisions and the appropriateness of industry self-regulation versus government intervention in food marketing. This chapter will explore the dietary and health implications of children's exposure to unhealthy food marketing and present arguments for and against regulations to restrict this marketing.