The goal of measurement is to drive a change. Therefore, measures should help people understand the behavior of a system and take steps to improve its performance. Measurement must also help stakeholders respond to the constant change in communities and the dynamics of any initiative. How can measurement support an adaptive change process in a community system striving to optimize population well-being? How can integration and management of data collection and analysis work in practice? This case study of the Magnolia Community Initiative describes such a measurement system, and offers it as an example to illustrate a set of principles for measurement.