In2O3:Sn (ITO) films has been prepd. by RF sputtering at 380 Deg with the O admixt. to the sputter gas being varied systematically. At a low O flux, the (400) grains are much larger than grains with other orientations. With increasing O flux, grain diam. and free electron concn. decrease and the texture of the crystallog. orientations changes from (400) to (622) dominant. It is suggested to est. the fraction of material with a certain orientation by the product of height and 3rd power of the width of the corresponding x-ray peak. This yields the same total x-ray scattering intensity for all samples. The structural properties are explained by a model of dynamic incorporation and segregation of O during film growth. The electron mobility as a function of the electron d. roughly follows a power law similar to that of single crystals, indicating that it is dominated by scattering at ionized donors.