Flexible operation and related power changes can have a direct impact on fuel integrity through pellet–cladding interaction/stress corrosion cracking (PCI/SCC) phenomena, which could lead to fuel failures in certain conditions. For some anticipated operational occurrences that affect fuel with small PCI/SCC margins, the fuel failures caused by PCI/SCC cannot be assumed to be benign, and a significant radiological source term may be generated. This publication provides an overview of PCI/SCC studies and reports on the progress made since the early 2000s, based on presentations and discussions at a related IAEA technical meeting held in October 2019.