Abstract: A work shelf for removable installation and use on a stepladder to provide an enlarged, sturdy area for holding tools and material. The work shelf includes a platform area of a width greater than the distance between the ladder rear legs, a neck extending from one edge of the platform area and having a width less than the distance between the ladder rear legs, and a brace extending from the neck and having a width less than the distance between the ladder front legs. A retaining edge extends up from the platform area. In use, the platform area overlies and is supported on the stepladder shelf, while the neck extends between the ladder rear legs, and the brace is positioned between the ladder front legs and beneath one of the ladder steps. A clamp is movably fastened to the neck. With the work shelf in position on a stepladder the clamp is secured in a position abutting the ladder rear legs.