This research is on adiabatic logic design for very low energy consumption circuits and systems. The primary idea is to use principles of adiabatic switching as the basis for circuit design. Energy recovery using this notion is a relatively new idea, although the concept of reversible logic and zero-energy computing can be tracked back to he early 1970s, the attempt to realize the concept in electronic circuits is a new endeavor. An adiabatic logic, using both fully reversible and partially reversible logic, is being developed. It is based on standard CMOS technology with a switching power supply. Basic logic gates, registers, and memories for recovered energy operations, are being developed. Tools for power management, such as techniques to utilize the redundant signals generated from reversible logic gates, are being developed. The newly designed circuits and the corresponding power supply are being fabricated and tested.