The OPEN evaluation team presented at the state-wide MassCALL2 Evaluation Meeting in April. As part of the ongoing evaluation of the Cambridge Opioid Overdose project, which is aimed at reducing fatal and nonfatal opioid-related overdose in Cambridge, the team at ICH has collected and monitored local DAWN data, ambulance data and death certificate data. The presentation accomplished the following: 1) provided an overview of the data findings, 2) described the real and potential challenges with these data sources, and 3) shared some lessons learned for other communities to consider.