This book presents a rationale for developing new approaches to conceptualizing the costs associated with the implementation and operation of models supporting comprehensive, community-based support systems (CCBSS) for children. CCBSS are broad-based approaches that have no single model or specification for reform; the configuration of the model is dependent on the needs, values, and perspectives of the community in which it is developed and implemented. Sections of this paper discuss various models in terms of conducting a flexible community-based cost analysis, identifying the resources needed to support the model, adjusting for marginal cost, and the distribution of cost. A cost template is presented to guide local policymakers through a systematic consideration of the total and marginal costs of the resources necessary to operate CCBSS models in their own communities. The template is intended to be a useful tool for policymakers in early planning stages--as well as those interested in monitoring the costs of initiatives already in operation--to gain a better sense of the types, amounts, and distribution of costs associated with various models of CCBSS. The template is applied to a sample model of a CCBSS. A final section draws conclusions from the previous sections and suggests next steps that should be taken in field-testing and expanding the template. (ET)