This paper covers the risk-based inspection (RBI) practices to address external corrosion under insulation (CUI) and corrosion under fireproofing (CUF). The paper discusses risk-based inspection practices of the external corrosion of carbon and low-alloy steels under insulation and fireproofing and the external chloride stress corrosion cracking (ECSCC) of austenitic and duplex stainless steels under insulation, and the external stress corrosion cracking of carbon steel under mineral wool insulation. The RBI methodology described consists of 4 steps, including unit level prioritization, challenging the need for insulation, data validation, and detailed RBI analysis. These steps work together to identify units at higher risk of CUI and CUF, develop an appropriate inspection plan to mitigate CUI and CUF, enhance personnel safety, and reduce unnecessary expenditures. The risk of CUI and CUF failure can be quantified by considering the likelihood of occurrence and severity of consequence.