The National Aeronautics and Space Administration (NASA) is seeking partners for the Medium Explorer (MIDEX) mission, specifically to serve as satellite integrators for the development of a spacecraft bus and related support for a Class C mission. This opportunity involves providing integration and environmental testing support, as well as optional mission operations center services, aligning with the objectives outlined in the 2013 Decadal Survey for space exploration. The total proposal cost cap is set at $300 million, exclusive of the launch vehicle, with key deadlines including a detailed presentation submission by January 6, 2025, and a draft announcement expected in April 2025. Interested parties can contact Barbie Medina at Barbie.Medina@nasa.gov or Kelly Collins at kelly.collins@nasa.gov for further information.