Infectious disease outbreaks have become increasingly common and require global partnership for adequate preparedness and response. During outbreaks, medical countermeasures (MCMs)-vaccines, therapeutics, and diagnostics-need to reach patients quickly. BARDA utilizes public-private partnerships to support advanced development of MCMs through U.S. FDA approval against a variety of threats within its mission space. MCM preparedness and response must be approached as an integrated life cycle, not as independent steps. Recent filovirus outbreaks in Africa exemplify that collaborative relationships are critical for emergency response, and products with regulatory approval can expand access and reach patients quicker than investigational products. Unfortunately, insufficient funding globally and differences in funders’ prioritization puts gains and future efforts at risk. Of primary concern is a) lack of a feasible regulatory path and clinical capability to achieve regulatory approval for new MCMs for many diseases; and b) the need for partners with the mandate, funding, and capabilities to support the life cycle activities following development-long-term sustainment of manufacturing capability and stockpiling of licensed products to support international outbreaks. Finding partners that complement BARDA’s mission and support the MCM life cycle will be a key component in deciding which MCM development efforts can be supported. Without collaboration, the global community runs the risk of losing the capabilities built through years of investment and being underprepared to combat future threats. Synergies between funders that have different roles and responsibilities within the MCM life cycle are critical to MCM availability and create long-term sustainment of products to ensure access.© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America.