Systems theory [1,2] suggests that healthy communities promote healthy individual development. That is, healthy systems take care of their component parts, and they do this, in part, by conducting positive exchanges with external systems. However, the thinking on what characterizes a "healthy" community continues to change over time. Social exchange theory [3] emphasizes the norms of reciprocity and the underlying relationships of trust that develop in healthy communities. Other authors stress the need for various forms of capital, not only economic and political, but also social, environmental, cultural, and spiritual [4,5].Contemporary theory underlying the trend towards "New Urbanism" [6] has its roots in the writings of Jane Jacobs [7]. Jacobs, a U.S. citizen, challenged the prevailing notions of urban planning in the United States, claiming that urban renewal of the 1940s and 1950s had hurt the health of cities due to single use zoning that located residents, parks, business, government services, etc. in separate sections of the city. This tended to leave these areas unused for extended periods of each day, thus isolating various groups and uses. She further insisted that high rise towers and open plazas created wind swept areas with little appeal to pedestrians, who preferred denser neighborhoods with short blocks and buildings of moderate height.Consequently, contemporary views of "livable communities" maintain that density and diversity are good for the health of cities. Healthy communities are more pedestrian-friendly and less automobile-centric. Mixed-use zoning keeps a flow of people through streets, neighborhoods, and districts, which is good for business, safety, and tourism. Locally-sourced food is more sustainable for the environment and healthier for individuals [7][8][9].But how does this all relate to the current and future provision of social services? And how should social institutions collaborate with those of the economic and political sectors to maximize individual and societal well-being? Those involved with the settlement house movement of the late 1800s and early 1900s in Great Britain and the United States certainly understood the impact of the environment on individual functioning and worked with both government and business leaders to better organize communities and services to meet the needs of residents. Deinstitutionalization and the movement toward community-based social services in the U.S. in the 1960s, 1970s, and 1980s recognized the potential positive influence of healthy communities on individual functioning [10,11].This special collection, therefore, aims to focus on the contextual factors that characterize "healthy communities" and that impact individual development and well being around the world. Researchers from various fields including psychiatry, public health, sociology, political science, community planning, economics, kinesiology, and social work present their theoretical, empirical, or practice-based studies on critical issues involving healthy communities.To begi...