Casing design advances today include risk-based Stochastic methods. The previous standard ''drop down and click'' methods do not consider strengths of new materials, and often are extremely conservative for many applications. Advanced strength theories and probabilistic performance properties today are used for extreme wells, including deep water and HPHT. API currently is considering updating its standards towards the new ISO 10400 limit states level, which will open the industry to a wider and more efficient use of today''s technologies. These issues will be presented, along with: sour design fracture mechanics-based criteria, and design of connections.