We introduce 3D diff, a novel approach to interactively resolve conflicting mesh edits. Our method performs conflict detection and visualization and allows the user to quickly select one of the two revisions for each conflicted scene graph (SG) node. By further integrating the knowledge about a common ancestor of the two models, a. k. a. 3-way diff, we are able to automatically resolve more conflicts than in a standard 2-way comparison. Our method is particularly useful for revision management of 3D models.