The demand for production inputs by the average property in the Australian sheep industry and substitution between these inputs was examined in this paper by estimating the set of input share demand equations derived from a transcendental logarithmic cost function. The following five input categories were examined: labour, land, livestock, capital, and materials and services. While the demand for labour was inelastic with respect to its own price, the demand for capital was elastic. All cross price demand elasticities estimated were less than one. In contrast with earlier Australian studies, the elasticity of substitution between labour and capital was found to be greater than unity. Technical change has been relatively labour and land saving and relatively capital, livestock, and materials and services using.