The Defense Advanced Research Projects Agency (DARPA) is soliciting innovative proposals to develop systemic drug delivery platforms for medical countermeasures (MCMs). The Hermes program is explicitly seeking transformative approaches enabling the development of delivery platforms with systemic biodistribution, exceptional endosomal escape efficiency, and minimal toxicity. Successful proposals will include a detailed description of the proposed delivery platform including 1) screening pipeline, 2) reporter systems for monitoring biodistribution and expression in animal models, 3) methods to monitor immunogenicity/toxicity, and 4) chosen therapeutic cargo and justification. Systemic delivery platforms developed under the Hermes effort will be transferred to U.S. Government stakeholders for further development.