Abstract: A stabilizing attachment for a ladder intended to make the ladder safer to use. The attachment includes a fixture capable of being secured at a selected position along the length of the ladder and support means comprising a cross member extending parallel to the rungs of the ladder and a pair of parallel struts coupling the cross member to the fixture. The support means can be arranged in either of two positions; in one position, the struts extend at right angles to the uprights of the ladder while in the other the struts extend parallel to the uprights. In either case, the cross member makes line contact with the structure against which the ladder is placed and the cross member may be provided with a friction-engendering surface to inhibit slipping of the cross member on the structure.