A vapor-phase carbonylation method for producing esters and carboxylic acids from reactants comprising lower alkyl alcohols, lower alkyl alcohol generating compounds, and mixtures thereof. The method includes contacting the reactants and carbon monoxide in a carbonylation zone of a carbonylation reactor under vapor-phase carbonylation conditions with a catalyst having a catalytically effective amount of a Group VIII metal selected from platinum or palladium, and tungsten which are associated with a solid catalyst support material.