The U.S. Army Research Office (ARO) in partnership with NSA's Laboratory for Physical Science (LPS) is soliciting Incubator, Collaboration, and Fellowship research proposals for participation in the LPS Qubit Collaboratory (LQC). The mission of the LQC can be captured in three broad goals: 1) pursue disruptive fundamental research and enabling technologies with a focus on qubit development for quantum computing and other applications (such as sensing); 2) grow deep, collaborative partnerships to tackle the most difficult and relevant long-term problems in quantum information science and technology; and 3) build a quantum workforce of tomorrow through research experiences in government at LPS and at LQC partners. The LQC will offer a mechanism for collaborative research between LPS and academia, industry, FFRDCs, and Government Laboratories to advance foundational and transformative research on challenging problems that have hindered progress in quantum information processing and associated technologies. The goal of this BAA is to seek proposals that bring together expertise from the public and private sectors and their respective research infrastructures to advance solutions that may be best approached as a collaborative team. A Collaboratory is “a center without walls, in which the nation's researchers can perform their research without regard to physical location, interacting with colleagues, accessing instrumentation, sharing data and computational resources, [and] accessing information in digital libraries. This BAA introduces LQC Research Thrusts ( A.1.1 ) which are the technical areas of interest—which will be updated periodically—where partners of the LQC will pursue joint research with LPS through Incubator ( A.1.2 ) and Collaboration ( A.1.3 ) collaborative agreements. The LQC BAA also fulfills the Government's overarching interest--through the proposed research and on-site research experiences--in creating and training a workforce in quantum science and technology, generating pathways of solutions that feed technology development, establishing partnerships, and creating transition opportunities. In further support of training through research, Section A.1.4 calls for Quantum Computing Research (QuaCR) Graduate and Postdoctoral Fellowships for US citizens working in areas of interest as described below. Substantial progress on solving the most difficult and long-term Quantum Information Science & Technology (QIST) research problems that unleash further rapid progress in the field will constitute LQC success. Examples of such research problems include (but are not limited to): limits of performance due to device design, material selection, and/or control, the exploration of alternative qubit physics (e.g., different approaches to qubit encoding or types of gates) and lowering of barriers to such approaches, advances in materials that improve qubit gate fidelity, reducing the overhead of classical components in quantum information techno…