The goal of this project is to develop a Wireless, fully Implantable, bidirectional Cortical Neuroprosthetic System (W-ICONS) for restoring sensorimotor function through an interface with intact upper limb areas of primary motor and sensory cortex. Technologies that enable direct communication to and from the brain have increasingly shown promise for restoring independence to people affected by high spinal cord injuries. Despite these advances, neural interface systems are still mostly confined to laboratory settings, requiring a team of researchers to handle cumbersome transcutaneous interfaces, extensive wiring, and bulky devices for recording and stimulating neural activity. Further, these devices have typically been equipped exclusively with neural recording capabilities. The W-ICONS device would be the first wireless, bidirectional—incorporating neural recording and stimulation—cortical implant for tetraplegic individuals, creating a truly portable device for use outside the lab environment. This proposed translational study benefits from over a decade of clinical studies with microelectrode arrays, demonstrating safety and efficacy in restoring lost sensorimotor functions. The Brain Gate and Revolutionizing Prosthetics clinical trials have demonstrated that functionally relevant control over prosthetic arms and communication devices can be achieved and maintained for years. More recent studies from a number of groups (including our own) have shown that intracortical microstimulation (ICMS) can provide stable, localized sensory percepts capable of improving task performance on reach-and-grasp tasks. Critically, our team has led and received FDA and institutional regulatory approvals for four first-in-human demonstrations. Here, we will be extending our team’s state-of-the-art fully implantable wireless recording system with the addition of stimulation capabilities. Benchtop verification of the W-ICONS system (Aim 1), will be followed by preclinical testing of the device in an animal model, will support an FDA IDE submission (Aim 2) to conduct an early feasibility study (Aim 3) at JHU of the W-ICONS with individuals affected by high spinal cord injury (tetraplegia). The aim of the clinical study at JHU is to validate chronic safety and efficacy of the W-ICON system in two participants in a 1-year study (minimum). Safety will be demonstrated if the device is not explanted due to safety reasons during the study period. Demonstration of efficacy will require control of sensorized robotic arms in pick- and-place tasks (e.g., Action Research Arm Test) and reported perception of ICMS in the hand area. Successful demonstrations will support a study protocol amendment to go beyond one year of implantation and to transition use of the device to patients’ homes.