Abstract: This paper presents an algorithmfor determining the paths along which corresponding vertices travel in a 2-D shape blending. Rather than considering the vertex paths explicitly, the algorithm defines the intermediate shapes by interpolating the intrinsic definitions of the initial and final shapes. The algorithm produces shape blends which generally are more satisfactory than those produced using linear or cubic curve paths. Particularly, the algorithm can avoid the shrinkage that normally occurs when rotating rigid bodies are linearly blended, and avoids kinks in the blend when there were none in the key polygons.