A stage (50; 150; 250; 350; 450) of a gas turbine engine, comprising: a row of flow directing components (52; 152; 252; 352; 452) circumferentially disposed about a centerline axis and each comprising a respective airfoil; and at least one flow directing component (52;...452) of said row having at least one design characteristic that is dissimilar from a corresponding design characteristic of at least one other flow directing component (52;...452) of said row; characterised in that: said at least one design characteristic is one of: an airfoil pitch; an inner platform endwall contour, wherein the inner platform endwall contour includes at least one undulation comprising a peak and a valley, the peak directly adjoining a pressure side of the airfoil adjacent to a leading edge of the airfoil, and the valley directly adjoining a suction side of the airfoil aft of the leading edge; or both said inner platform endwall contour and an outer platform endwall contour, wherein one of the inner platform endwall contour or the outer platform endwall contour includes at least one undulation comprising a peak and a valley, the peak directly adjoining a pressure side of the airfoil adjacent to a leading edge of the airfoil, and the valley directly adjoining a suction side of the airfoil aft of the leading edge. a row of flow directing components (52; 152; 252; 352; 452) circumferentially disposed about a centerline axis and each comprising a respective airfoil; and at least one flow directing component (52;...452) of said row having at least one design characteristic that is dissimilar from a corresponding design characteristic of at least one other flow directing component (52;...452) of said row; characterised in that: said at least one design characteristic is one of: an airfoil pitch; an inner platform endwall contour, wherein the inner platform endwall contour includes at least one undulation comprising a peak and a valley, the peak directly adjoining a pressure side of the airfoil adjacent to a leading edge of the airfoil, and the valley directly adjoining a suction side of the airfoil aft of the leading edge; or both said inner platform endwall contour and an outer platform endwall contour, wherein one of the inner platform endwall contour or the outer platform endwall contour includes at least one undulation comprising a peak and a valley, the peak directly adjoining a pressure side of the airfoil adjacent to a leading edge of the airfoil, and the valley directly adjoining a suction side of the airfoil aft of the leading edge. an airfoil pitch; an inner platform endwall contour, wherein the inner platform endwall contour includes at least one undulation comprising a peak and a valley, the peak directly adjoining a pressure side of the airfoil adjacent to a leading edge of the airfoil, and the valley directly adjoining a suction side of the airfoil aft of the leading edge; or both said inner platform endwall contour and an outer platform endwall contour, wherein one of the inner platform endwall contour or the outer platform endwall contour includes at least one undulation comprising a peak and a valley, the peak directly adjoining a pressure side of the airfoil adjacent to a leading edge of the airfoil, and the valley directly adjoining a suction side of the airfoil aft of the leading edge.