Type 308 stainless steel containing niobium is often used in high temperature applications. Welding is normally resorted to for joining purposes in such components. The crack growth behaviour in the weldment of 308 S.S. has been studied in the temperature range of 600 to 800°C. The stress intensity factor, the COD approach and the energy rate line integral have been tried to correlate the crack growth rate. Crack growth takes places along the interphase between the austenite and the primary arm of the delta ferrite at 600°C. At higher temperatures sigma phase becomes more dominant in the crack growth process. © 1989.