The Pourbaix diagrams (potential-pH diagrams) for chromium at 25-300°C have been revised. The diagrams were calculated for two concentrations: 10 - 6 and 10 - 8 molal. Extrapolation of thermochemical data to elevated temperatures has been performed with the revised model of Helgeson-Kirkham-Flowers, which also allows uncharged aqueous complexes, such as Cr(OH) 3 (aq), to be handled. The calculations show that the hydroxides Cr(OH) 2 , Cr(OH) 3 , and the oxides CrO 2 and CrO 3 are not stable at the investigated temperature and concentration interval. Cr 2 O 3 is the only stable solid chromium compound in aqueous solution in the environment studied, with the exception of very diluted solutions such as 10 - 8 molal at T > 150°C, where no solid chromium compound is stable. The dichromate ion does not predominate anywhere within the calculated concentration range.