Abstract: A ladder that includes two hinged sections that can be oriented in an inverted V-configuration for use as a step ladder, or in a straight linear configuration for use as a straight ladder. Each section of the ladder includes a number of U-shaped support units, each of which defines a crossbar and two downwardly extending side rails. The side rails of the different U-shaped units are of graduated cross sectional dimension, such that the units can be contracted together by telescopically sliding the aligned side rails within one another.