The model for school-linked services is based on the ideal of providing a coherent and seamless web among school professionals and other service agencies. However, schools are often organized around specialized functions that are not wholly aligned and coordinated in function and purpose. This paper examines the nature of schools as "aggregative" (as opposed to "integrative") organizations and the implications for implementation of an integrated, school-linked-services reform initiative. The theoretical framework of "new institutionalism" (March and Olsen, 1984; Powell and DiMaggio, 1991) is used to analyze the design and implementation of a neighborhood-based, school-linked-services effort, referred to as Community-Based Collaboration for Families (CBCF), in a medium-sized midwestern city. Data were obtained from a longitudinal, qualitative analysis of three urban schools and a low-income neighborhood. The paper suggests that reform initiatives such as school-linked services fail to consider the nature of school organization, thereby contributing to the aggregative, rather than coordinated and systemic, functions of schools. Although the services might be integrated, the school as an organization is not: the aggregative school design, which institutionalizes functions into a set of subsystems, contrasts with the coherent, integrative purpose and structure of integrated services. Reforms therefore constitute "add-ons." No matter how tightly integrated and collaborative the school-linked-services model, the school organization is not designed to respond similarly. (Contains 31 references). (LMI)