DARPA will host a Proposers' Day conference in support of the DARPA-BAA-14-32, Tactical Undersea Network Architectures (TUNA) program on Monday, April 28, 2014 from 8:30a.m. to 12p.m. Eastern Daylight Time at the DARPA Conference Center, 675 N. Randolph St, Arlington, VA 22203. The purpose of this conference is to provide information on the TUNA program; promote additional discussion on this topic; address questions from potential proposers; and provide a forum for potential proposers to present their capabilities for teaming opportunities. Refer to the attachment, "DARPA-SN-14-34 - TUNA Proposers Day," for further details of this Special Notice.