Abstract: A waste container reformer, for reforming generally disk-shaped compacted waste containers into prismatic forms, sequentially presses the sides of the waste container into a prism with a 45.degree.-90.degree.-45.degree. triangular base so that when it is placed adjacent to another reformed container, the two form a rectangular box for more efficient use of storage space. The pressure surfaces are controlled by hydraulic cylinders to provide the forces needed to reform the container. The reforming process is controlled so that one angle is formed at a time, beginning with one of the 45.degree. angles, followed by the 90.degree. angle, and then completed by forming the other 45.degree. angle. By forming one angle at a time, the load requirements of the reformer are reduced, and a consistently similar shaped reformed waste container is created.