 His research contributions include mechanisms of action in community-based approaches to tobacco-, alcohol-, and drug-abuse prevention.His recent research has focused on social and cultural change acting in combination with genetically and environmentally driven dispositional characteristics to influence health risk behaviors, including socio-cultural and dispositional interactions influencing the effectiveness of smoking and alcohol abuse prevention programs.He is the founding director of the China Seven Cities Study, a longitudinal study of tobacco use and lifestyles in seven of China’s largest cities.