Extensive data have been obtained in the last decade in this program and other international programs that show that Alloy 690 and its weld metals inherently have at least some susceptibility to stress corrosion cracking(SCC).Low growth rates are observed under good circumstances,but there are vulnerabilities that can increase the growth rates by 1000X.The primary vulnerabilities evaluated relate to microstructural homogeneity and cold work,and above~20%cold work high crack growth rates are often observed.This sensitivity to cold work is applicable to most,if not all,heats and forms of Alloy 690,although reduced grain boundary carbide coverage reduces the vulnerability.This talk presents on-going work on the effect of cold and hot work,solution annealing and the orientation of the crack plane in relation to cold work on many heats of Alloy 690 ranging from plates to control rod drive mechanism(CRDM)housings.This talk also briefly summarizes extensive testing on Alloy 152 and 52 weld metals,which consistently show very low growth rates in the as-welded condition.