Cardiac assist devices are increasingly being used for long term support. As patient survival times increase substantially, long-term management of the patients will increasingly play a role in suitability of these devices as destination therapies. Infection, primarily due to cable entry site(s), remains a primary complication for these patients. To-date, the only practical approach to completely eliminate long-term issues associated with cable entry site infections is to use a TET (Transcutaneous Energy Transfer) system. A TET system, is an electro-magnetic power transfer system, which can send substantial electrical power across a patient's intact skin, thereby eliminating cable entry site infections. The ultimate objective of the research proposed here is to develop a fail-safe TET system with substantial reduction in power transfer sensitivity to patient movement. ABIOMED has already developed a first-generation TET system currently in use in the clinical trial of the AbioCor total artificial heart. This system, although highly effective in a clinical setting, has demonstrated the need for a fail-safe operation as well as for reduced sensitivity to patient movement. Starting with the current ABIOMED TET as a base, detailed studies in phase I will develop a novel, fail-safe TET system and fully characterize its performance. The need for a trouble free, user friendly TET system is already very visible, and will become increasingly important as more patients are discharged home with destination cardiac support prostheses. For these patients a robust, lightweight, complication-free power source will play a critical role in achieving a near-normal quality of life.