This Request for Information, DARPA-SN-16-58, from the Defense Advanced Research Projects Agency's (DARPA) Tactical Technology Office (TTO) seeks ideas, methodologies, and approaches solely for information and planning purposes. DARPA is interested in identifying novel, flexible, mobile layered defense systems and component technologies that could be leveraged to improve force protection against a variety of sUAS threats and tactics, could be fielded within the next three to four years, and are structured to rapidly evolve with threat and tactic advancements. DARPA is interested in exploring the potential for developing and demonstrating system solutions, including sensors and effectors, to enable detection, identification, tracking, and neutralization of sUAS threats. The solution should be scalable and modular such that it could be deployed in multiple defense applications on a variety of platforms (vehicles and vessels); the solution is intended for the defense of fixed and mobile ground and naval forces. To the greatest extent possible, it should also address rocket, artillery, mortar, and other conventional threats. System flexibility, deployability, and affordability will be major design drivers, as the system will only be an effective deterrent and defensive capability if it can be widely deployed to protect a large number of assets. Therefore, this RFI seeks information on concept performance capabilities, unique and enabling technologies, technology maturity levels, system architecture, concepts of operations, and system affordability. Responses to this RFI will be used to determine attendees for a workshop in Arlington, VA. In addition, the information may potentially support the development of new DARPA programs that could enable a revolutionary layered defense approach to achieving mobile force protection, including counter-unmanned air systems (CUAS) capabilities. Refer to the attachment for a complete copy of this RFI.