The shape property of transposed pottery sherds that changes most rapidly due to wear during water transport in natural sedimentary environments is roundness, the degree of curvature of edges and corners. Of the many methods for the measurement of particle roundness, which are briefly reviewed, that proposed by Wadell (1932, 1933) is considered to specify roundness best. A simple and rapid procedure for the measurement of the Wadell projection roundness is described, which yields roundness values having a precision of the order of a few percent, the precision improving with the degree of roundness. The technique is therefore suitable for the analysis of large samples of transposed and transported sherds.