This paper focuses on the impact of economic and demographic variables on agricultural productivity. The purpose of this study was to examine resource productivity on farms in selected areas of County Mayo. The returns to land, labor, livestock investment, and variable nonlabor costs were examined for possible resource misallocation. The impacts of age of decision maker and family size on gross output were also studied. Knowledge of the productivity of resources used in the production processes of farmers in County Mayo should be of interest to the farming community, extension agents, banks and lending agencies, policy makers, and all concerned with the development of agriculture in the west of Ireland.