ABSTRACTThe user-managed inventory (UMI) is an emerging idea for enhancing the current distribution and maintenance system for emergency medical countermeasures (MCMs). It increases current capabilities for the dispensing and distribution of MCMs and enhances local/regional preparedness and resilience. In the UMI, critical MCMs, especially those in routine medical use (“dual utility”) and those that must be administered soon after an incident before outside supplies can arrive, are stored at multiple medical facilities (including medical supply or distribution networks) across the United States. The medical facilities store a sufficient cache to meet part of the surge needs but not so much that the resources expire before they would be used in the normal course of business. In an emergency, these extra supplies can be used locally to treat casualties, including evacuees from incidents in other localities. This system, which is at the interface of local/regional and federal response, provides response capacity before the arrival of supplies from the Strategic National Stockpile (SNS) and thus enhances the local/regional medical responders' ability to provide life-saving MCMs that otherwise would be delayed. The UMI can be more cost-effective than stockpiling by avoiding costs due to drug expiration, disposal of expired stockpiled supplies, and repurchase for replacement.(Disaster Med Public Health Preparedness. 2012;6:408-414)