Techniques for interactive deformation of unstructured polygon meshes are of fundamental importance to a host of applications. Most traditional approaches to this problem have emphasized precise control over the deformation being made. However, they are often cumbersome and unintuitive for non-expert users. In this paper, we present an interactive system for deforming unstructured polygon meshes that is very easy to use. The user interacts with the system by sketching curves in the image plane. A single stroke can define a free-form skeleton and the region of the model to be deformed. By sketching the desired deformation of this reference curve, the user can implicitly and intuitively control the deformation of an entire region of the surface. At the same time, the reference curve also provides a basis for controlling additional parameters, such as twist and scaling. We demonstrate that our system can be used to interactively edit a variety of unstructured mesh models with very littl...