Many tools have been developed for recovering the design of legacy software. Interactively invoked abstraction operations and re-design transformations play a central role in these tools. A limitation of most existing approaches is, however, that they assume a mostly linear transformation process. They provide little support for iteration, recursion and incremental changes during the recovery process. Nevertheless, empirical results suggest that real-world abstraction and reengineering processes are in fact highly iterative. A history mechanism that explicitly maintains dependencies of all performed transformations can overcome this mismatch. Based on our experience with a specialized implementation of such a mechanism, we present a generalized history concept as an add-on to existing tools that support design recovery.