A series of austenitic alloys (800H, H214, I625, 310S and 347) were exposed to supercritical water at 550 ºC and 25 MPa for 260 h and 450 h in a static autoclave with an initial level of dissolved oxygen of 8 ppm. Cross sections of oxidized samples were imaged with SEM and analysed with EDS for the composition of the oxide layer(s). Indentation with a hardness indenter was used for assessment of oxide adhesion. Mass loss was obtained through descaling. Two surface finishes were applied - a coarse grinding with 120 grit abrasive (applied by the manufacturer) or polishing with either 1200 grit, 1 ?m diamond or 0.05 ?m alumina suspension. The only sample which delaminated during indentation was polished H214 (both alumina and 1 ?m).