New York City gained more than 1,100,000 residents in the two decades between 1980 and 2000, and its neighborhoods experienced substantial demographic and social change. Evidence of the changing service needs is demonstrated by the growth of the Latino population by 770,000, Asian-Americans by 550,000, African-Americans by 270,000, and other immigrants by 300,000, while the white population declined by 790,000. An increase in economic disparities has accompanied these population shifts that is strongly in evidence at the neighborhood level. The city’s neighborhoods of concentrated poverty, for instance, grew by almost 200,000 during this period, including 50,000 additional children below 13 years of age. These neighborhood changes have very much altered the demand for services in the City, especially the demand for immigrant services. Why does it matter how immigrant services are distributed within cities like New York? Three factors are emphasized in this paper: access, responsiveness, and coverage. Accessibility or proximity of these services is vitally important to users, contributing to the development and maintenance of social network and social support systems. Organizational responsiveness to neighborhood diversity, disparities, and evolving service needs is especially relevant where neighborhoods are socially and ethnically distinctive, as in New York. Finally, analysis of neighborhood coverage, including service gaps and saturation, is essential because nonprofit service providers function independently without an overall framework to ensure matching of service provision to needs. Access, responsiveness, and coverage matters a great deal to immigrant service organizations as well as to users and funders of their services, including government agencies, foundations, businesses, and private donors concerned with equity and effectiveness in service delivery. Yet, many nonprofit organizations do not provide direct services to local immigrant residents, but serve citywide, national, or international constituencies or carry out primarily administrative and fund-raising activities in their city offices. Issues of access to local users and adequate neighborhood coverage may be less important for these organizations. However, their concentration or dispersal within the city is still highly significant because many of these facilities (e.g. museums, universities, and hospitals) have important “spill-over” benefits on their neighborhoods, especially on immigrant neighborhoods. This paper examines these location issues for New York City’s immigrant service sector in the context of the city’s diverse neighborhoods. The intention here is to relate the city’s complement of immigrant service organizations with the characteristics of neighborhoods where nonprofits have their facilities, i.e., to take an ecological approach to the presence of nonprofit immigrant services within the city. Our task is to assess nonprofit coverage of New York City’s immigrant communities and evaluate the added current challenge to nonprofits of responding to the rapidly changing demography, social structure, and service needs of the city’s neighborhoods. The information about immigrant service organizations in this paper comes from the U.S. Internal Revenue Service’s Core File based on returns (Form 990) filed for the year 2001 by New York City nonprofits and processed by the Urban Institute’s National Center for Charitable Statistics. Supplementary information about these organizations was obtained from the survey of over 3,000 nonprofits in New York City carried out by the New York City Nonprofits Project, City University of New York. Street addresses of these service organizations were transformed into x and y coordinates for the GIS analyses of the geographic patterns and to locate the organizations within New York City’s 59 community districts. Demographic, social, and other information about the city’s neighborhoods comes from InfoShare data maintained by Community Studies of New York, Inc.How well are the city’s immigrant service organizations matched with the immense variety of neighborhoods and communities in this complex city? The location analysis requires development of methodological tools, including functional classifications of both nonprofit service activities and types of neighborhoods, as well as indicators of goodness of fit of immigrant service facilities to neighborhood needs. Preliminary findings point to service gaps in rapidly changing low-income ethnic communities and outlying residential neighborhoods, and an over-concentration of facilities in downtown commercial areas. The geographic pattern is not ideal, even after allowing for land use zoning and neighborhood variations in factors affecting service demand. The findings have imperatives both for nonprofits and public officials through remedial efforts they can carry out to improve the fit of services to needs. The study and its methodology may provide some guidance for analyses of service location and proximity issues in other cities, regions, and states. In this paper, special emphasis will be given to the importance of:_ formulating a classification of immigrant services relevant for the specific locale;_ developing a classification of neighborhoods or other sub-areas based upon commonalties in expected service needs;_ using Geographic Information Systems (G.I.S.) for mapping and analyzing the geographic location of facilities;_ using econometric methods for testing the relationships between facility location and neighborhood contexts; and_ devising suitable measures of the goodness of fit of types of service activities to types of neighborhood conditions.