This course covers, in depth, the causes of corrosion. Starting by thoroughly reviewing the fundamental thermodynamic driving force of corrosion. We will look at the effects of operating environment and material of construction and explain their interaction in order to explain the corrosion phenomena. Control of corrosion, barriers, their durability, limitations and applicability will be also looked in-depth. At last, we will look at the various methods how to inspect for corrosion and how to reliably establish credible corrosion rates based on various non-destructive and destructive measurements. New trends in online corrosion monitoring will be discussed.