This is a description of the evaluation of Reading Recovery (RR). RR is an early reading intervention serving about 125,000 children every year in about 8,000 U.S. schools. Its 15,000 teachers submit data on every child to the National Data Evaluation Center, which produces a report for each school, district and university involved with RR. Through the use of web-based technology, these reports are available virtually instantly at year-end. Their process and outcome data help stakeholders at all levels to engage in data driven collaborative inquiry and make informed decisions about the delivery of services.