WREN coaches, with local improvement teams, use the Plan-Do-Study-Act (PDSA) Cycle as the primary process for identifying ideas that could affect the system they are seeking to change. PDSAs provide discipline and structure to the inquiry, enabling teams to test changes on a small scale, build on the learning in a systematic way, and try the idea in various contexts before full implementation. PDSAs help teams make data-based decisions that avoid one-size-fits-all solutions.