This paper is the first of a two-part series on financing early childhood mental health services. It discusses the need for a systemic approach to financing early childhood mental health services and supports and presents a matrix to assist states and communities in the design of comprehensive financing systems. The vertical axis of the matrix lists a range of early childhood mental health services and supports. The list of potential financing resources, displayed horizontally across the top of the matrix, includes the major federal, state, and local government and non-government sources of funding available to states and communities. To use the matrix, members of a state or community team would begin by taking an inventory of both existing services and funding sources. The inventory of services currently in place completes the vertical dimension of the matrix and its inventory of current funding sources goes in the matrix's horizontal dimension. Once the matrix is complete, areas where additional services and/or funding resources are needed and where any gaps or overlaps exist can be identified. Appendix A contains a blank matrix. Each of the funding resources is further described in Appendix B. (Contains 11 references.) (CR)