The Defense Advanced Research Projects Agency (DARPA) is hosting a Proposers Day for the Trenton program on October 10, 2024, via webinar. This event aims to inform potential proposers about the development and optimization of underwater three-dimensional concrete printing (3DCP) technologies, specifically focusing on utilizing seawater and seafloor materials for constructing concrete structures relevant to Department of Defense applications. The Proposers Day will feature presentations from DARPA personnel, followed by a question and answer session, and is designed to foster collaboration among researchers while enhancing understanding of DARPA’s initiatives. Registration is mandatory by October 4, 2024, and interested participants can reach out to the Coordinator at DARPA-SN-24-108@darpa.mil for further information.