This guide was developed to assist states and researchers in conducting a child care market rate study using the CCR&R data. States may be interested in using this approach, given that use of CCR&R data: (1) supports analysis of statewide market rates and geographic distribution of rates; (2) facilitates analysis of child care accessibility for those receiving child care subsidies; (3) provides convenient, inexpensive, and accessible data; (4) facilitates comparison of market rates over time; (5) reflects the complexity of the child care market; and (6) includes providers who are regularly and actively seeking business. Although several guides have been written that discuss how to conduct a market rate study using surveys, the contribution of this guidebook is to illustrate how Oregon has used CCR&R data to study market rates and to highlight the strengths and weaknesses of this approach. Description of this market rate methodology also lays out lessons learned from the work of the Oregon Child Care Research Partnership in its efforts to build a body of policy-relevant research methodology.