The aim of this proposal is to design, fabricate, and test a novel, flexible printed lead body for chronic implantation as part of peripheral nerve stimulation systems. Treatment modalities that require nerve stimulation include restoration of motor control and sensation following paralysis or amputation, and chronic pain management. This study will focus on the use of NanoJetTM technology to print electronic traces with a novel design that will allow for strain relief under static and cyclic loading conditions. The flexible, printed lead body will be comprised of a flexible substrate, printed metallic ink, and protective barrier to allow for chronic functional and mechanical reliability. The lead body design will be created to connect with a percutaneous pain management system of which the mating ends will be customized for the application. Tasks to be accomplished under this proposal include the design, fabrication, and characterization of the device and its connecting ends. Long-term structural biocompatibility will be assessed through a series of static and cyclic mechanical tests and in vitro experiments that will establish chronic functionality. Passive implantation of the device will also provide information on general biocompatibility. Data collected through evaluations made with test specimens will feed into the design optimization process and data from full device testing will facilitate future applications to the FDA to perform follow-on animal studies and future clinical work. The proposed effort seeks to improve rehabilitative patient care and the quality of life of Veterans through the advances associated with the flexible, printed lead body. Implantable neurostimulation systems with high channel counts provide the best option for nerve selectivity, and if those can be provided in a robust, miniaturized system that allows for a minimally invasive procedure, then new opportunities for the development of percutaneous pain management can be realized. Additionally, existing implantable systems for neurostimulation may benefit from the high-density flexible lead, which would minimize the concerns related to complex implantation procedures and larger volumes of implanted materials for the same number of channels.