The science behind the headlines is explored in the Big Picture series launched by the Wellcome Trust. This successor to LabNotes is published twice a year for post-16 teachers and students. It provides an in-depth look at issues relating to biomedicine and looks at moral, political and social implications related to the topic. The current issue on obesity includes articles on metabolism, food advertising and marketing, the psychology of gratification, genetics and fat, and the media and the "obesity timebomb". Teacher's copy is available free, class sets are pound;1 per copy per issue for 2-20 copies (inc pp), or 75p for 20 copies or more. Back copies can also be ordered from the website.