Healthy Cities is a community problem-solving process for health promotion that began in Canada and Europe in the mid-1980s. Although Healthy Cities have expanded worldwide, there is limited scientific literature that documents the effects of these efforts. This review describes the dynamic status of Healthy Cities globally and summarizes what is known about these efforts. It is difficult to draw generalizations or clear differences between Healthy Cities and other efforts with similar objectives in the United States. There appears to be less variation among Healthy Cities in Europe, most likely because of the extensive technical support provided by the WHO European Regional Office to the Healthy Cities Project. Case descriptions present the diversity and types of activities of Healthy Cities. It is concluded that community participation and broad involvement from different sectors of the community are promising approaches to addressing urban problems.