Since publication of the first edition of Pipeline Pigging and Integrity Technology 25 years ago, there have been massive advances the pigging and inspection industry: superb high-technology solutions have been developed, using some of the most advanced and reliable technology paralleling the aerospace industry, and feature assessments down to millimetric sizes are almost the norm. Inspection data interpretation has also developed to the stage where its no longer a black art: survey results can be examined and analysed on a clients own PC or laptop, the thought of which was almost unheard of...