We are currently developing techniques for visualizing collections of STEP files. Here we will describe the methods used and present preliminary results. Our preliminary results use small synthetic graphs as input to the system. In these examples the nodes may represent STEP files, and the edges represent references between them, just as the assembly of a large structure may reference smaller subassemblies. At another scale the graph may represent the structure within a single step file. It is important to note that the nodes and edges we visualize are not necessarily the vertices and edges of the 2D/3D geometry contained in a STEP file. We are developing large graph visualization methods as an approach to solving the problem of visualizing STEP data and the relationships among datasets in a repository.