Abstract: A portable and collapsible stair which provides support platforms that are spaced laterally and vertically from one another at approximately a one-to-one slope, thus enabling a person to ascend or descend the stair in a more convenient walking motion. There are two inverted U-shaped cross members pivotally connected to one another at a pivot axis intermediate the ends of the legs of the two U-shaped members. An upper support platform extends between the upper ends of the two inverted U-shaped members. There are one or more additional support platforms extending horizontally from forwardly positioned lower leg portions of one of the U-shaped members.