Have roast placed on platter, skin side up; with a pointed, thin-bladed, sharp knife out a sirloin or rib roast in thin slices parallel to the ribs, and cut slices from ribs. If there is tenderloin, remove it from under the bone, and cut in thin slices across grain of meat. Carve back of rump in thin slices with the grain of meat; by so doing, some of the least tender muscle will be served with that which is tender. By cutting across grain of meat, the tenderest portion is sliced by itself, as is the less tender portion.