Abstract: Given two or more geometric models, the goal of shape interpolation is to create a sequence of intermediate models which establish natural smooth transition between given shapes. We review existing shape interpolating approaches from the viewpoint of quantities of intermediate shapes obtained by linearly interpolating those of the given shapes. Some important properties of shape interpolating approaches are summarized, classification methodology is discussed, some important interpolation methods are described and commented, and their pros and cons are analyzed. Particularly, we investigate the ability of these approaches to deal with interpolation with large deformation. Finally, we draw some open problems in shape interpolation.