ISO/PAS 12835 is intended for assessment of casing connections for those field applications in which the design of the casing-connection system is strain-based, and in which primary axial loading is on the casing-connection system driven by constrained thermal expansion, and in which that primary loading exceeds the casing-connection system’s yield envelope. Consequently, ISO/PAS 12835 should be considered as a protocol that is complementary to ISO 13679, which applies to classic elastic-design applications.