195Pt solute diffusion coefficients in undoped single-crystal rutile TiO2 have been determined parallel to the c-axis over the temperature range of 10731523K and oxygen partial pressure of 101kPa. This has yielded the following temperature dependence: D195Pt=1.3 +/- 3.2x1013m2s1exp(122.0 +/- 13.6kJmol1RT) On the basis of this result, it has been concluded that 195Pt diffuses via an interstitial mechanism involving rapid transport parallel to the c-axis through open interstitial diffusion channels. While other divalent cations have also displayed diffusion via the same mechanism, and report diffusion rates that greatly exceed that for cation self-diffusion, the overall rate of 195Pt diffusion is slow. This has been attributed to the size of Pt2+ (0.80 angstrom) which is comparative to the dimension of interstitial channels (0.77 angstrom) through which transport is believed to be taking place.