A method of making a lens having adjustable optical power is disclosed. The lens is adjustable by relative lateral translation of at least two lens elements. The method may comprise providing a function yielding optical properties of the lens from starting geometries for the lens elements; refining the function to approximate required gaze angle optical performance over a range of said lateral translation; and using the refined function to derive geometries for making the lens elements. The function may comprise first and second functional parts respectively for the lens elements, and the method comprises using the function to derive geometries for making the lens elements, wherein the function relates optical path difference to a position across the lens elements, and the rate of change of curvature of the first functional part with position is different to the rate of change of curvature of the second functional part with position. There is also disclosed a lens having adjustable optical power. The lens is adjustable by relative lateral translation of at least two lens elements. The adjustable lens may be used for corrective eyeglasses.