This report describes the development of Retractable Bits (RBs) for drilling without the need to trip the drill string that has been ongoing in Russia during the past 50 years, including the latest research and field applications in offshore stratigraphic drilling projects. The potential to drill with fewer trips of the drill string significantly affects the process of borehole construction, sidetracking, as well as workovers. Other benefits of RBs include: 1. Continuous circulation of the borehole during the RB operational cycle (run in/drill/pull out) 2. Tools for a variety of operations (e.g., drilling, coring, milling) can be run in turn without pulling the drill string 3. The ability to log the borehole without pulling the drill string 4. Reduction of rig crew workloads