This series of worked examples is designed to illustrate as simply as possible the procedures in the second revision of CEGB Report R/H/R6 “Assessment of the Integrity of Structures Containing Defects” (1980). It is also intended to demonstrate how extra information may be gained by performing sensitivity analyses. The examples are artificial and the first 5 are based upon one type of problem, that of a crack in a pressurised cylinder. The level of complication is increased from one example to the next so that a working knowledge of the procedures can be built up to the level of sophistication needed. In the final example, the geometry of a crack in a flat plate is used to demonstrate how inconsistencies arise from the conventional application of rigid safety factors in fracture problems. Each example is structured so that it can be read without reference to the others.