Jurisdictions across the U.S. are looking to replicate and improve upon Oregon’s measure to decriminalize personal possession of drugs (Measure 110, also known as the Drug Addiction Treatment and Recovery Act of 2020). Comprehensive, effective, and rigorous evaluations are critical to measure the impact of the policy and to guide future efforts. Too often, however, researchers neglect to consult with people on the ground who are directly impacted by policy changes when they craft their evaluations and thereby miss important information and context. To encourage thoughtful policy evaluations, we convened an expert working group and conducted interviews with people in Oregon directly impacted by Measure 110 to craft evaluation principles and suggested metrics.