This is an individual chapter of Theory of Constraints Handbook. The purpose of this chapter is to share how successful adopters have put Critical Chain concepts into practice and achieved durable results. It is based on Realizationâ€™s experience from more than 200 Enterprise-level implementations of Critical Chain (meaning that the implementation was not restricted to a project manager or a small team, but involved multiple departments). The range of these includes: new product development; pharmaceutical R&D; development of IT applications; engineer-to-order manufacturing; shipbuilding; engineering, procurement and construction (EPC); and maintenance, repair and overhaul (MRO) of aircraft, submarines and ships, as well as steel plants and oil refineries. Starting with a quick recap of Critical Chain, it discusses practical challenges in implementing it successfully. Then, a step-by-step process of implementation is described, followed by an overview of lessons learned over the last ten years. Finally, before the summary, there are answers to the frequently asked questions that have not been covered in the rest of the paper.