World Health Report. Data were available for only 4 countries in Latin America. Unfortunately, if there are not adequate data to inform practice and policy, then physical inactivity will continue to be regarded as an issue of sports and recreation rather than a major public health risk factor requiring concerted action from all sectors of government and society at large. Great progress has been made in developing a simple instrument to assess physical activity and to provide information for use in population health surveillance systems. The International Physical Activity Questionnaire (http://www. ipaq. ki. se/) has been tested in 14 countries and is currently in use in several regional health promotion networks. It is also the core instrument in a large demonstration project involving 24 countries across all six WHO regions that is intended to collect a global sample of nationally representative data on physical inactivity. While there may never be the perfect set of questions to capture all the complexities of physical inactivity, the use of a standard measure allows comparisons within one country, between neighboring countries, and at a regional and global level. When comparable data exist, it is easier to share the experiences and lessons learned from such efforts as policy implementation, mass media campaigns, promotion of walking and cycling for transport, and other intersectoral actions that create environments encouraging active lifestyles.