Abstract: A prefabricated adjustable stairway having a pair of opposed stacked stringers supporting each step. A stair support bracket is pivotally attached to each top stringer and is connected by an associated link to the supporting bottom stringer. Each step is mounted on an opposed pair of brackets. Sliding movement of the top stringer on the bottom stringer is used to adjust each step to a horizontal plane regardless of the inclination of the stairway. The steps can then be fixed in this position.