Many successfully cemented wells begin to show annulus pressure buildup, which is often caused by damage to cement sheath integrity due to post-cementing operators. This problem may be temporarily dealt with by releasing the annulus pressure. However, this method of annular gas production is not a long-term solution to the problem. A finite element analysis (FEA) method has been developed to analyze the effects of various well events and operations such as cement hydration, casing pressure testing, completions and production on the integrity of the cement sheath during the life of the well. The three-dimensional FEA modelling considers the sheath's mechanical properties, such as Young's modulus, Poisson's ratio and tensile strength, in addition to confined compressive strength, and helps provide the user with a cement design that can maintain an annular seal over the life of the well. This paper discusses how a cementing design specialist can model the events upon and after cement placement to help provide a long-term seal of the annulus. The required input data is discussed and the output information is shown for example wells.