The mysteries of stress and its bodily effects revive old challenges and provide us with new ones. The BjArntorp Symposium, which is recorded in this volume, focused on the role of stress and the brain in the pathologic conditions of obesity and metabolic syndrome, including in their physiology, pathophysiology, socioeconomic consequences, and therapeutic interventions. Special emphasis was placed on the metabolic consequences of stress, which might contribute to the alarming increase in the prevalence of obesity and its comorbidities in recent years. The symposium and this volume are dedicated to the memory of a distinguished physician scientist, Professor Per BjA?rntorp, whose pioneering ideas and research have set the foundations in this important field and continue to be a source of inspiration. NOTE: Annals volumes are available for sale as individual books or as a journal. For information on institutional journal subscriptions, please visit www.blackwellpublishing.com/nyas. ACADEMY MEMBERS: Please contact the New York Academy of Sciences directly to place your order (www.nyas.org). Members of the New York Academy of Science receive full-text access to the Annals online and discounts on print volumes. Please visit www.nyas.org/membership/main.asp for more information about becoming a member.