The cement sheath is a crucial component of the wellbore system, responsible for maintaining structural integrity, and preventing leakage. Over the life cycle of oil and gas wells, load changes can lead to various cement failure modes, such as disking, radial cracks, and debonding fractures. It is vital to locate and evaluate cement sheath failure in the wellbore. This chapter aims to comprehensively and systematically describe recent advances in cement sheath integrity prediction, control, and monitoring techniques. Firstly, we list the underlying reasons for the cement sheath failure. Then, we extensively discuss current advances in cement sheath integrity. Finally, wellbore integrity control and monitoring techniques are also discussed. This chapter serves as a valuable reference for both scientific research and engineering applications of cement sheath integrity in oil and gas wells.