The renovation of buildings past their prime can no longer be regarded as a necessary evil that costs money and causes inconvenience. Increasingly, it is being acknowledged that to renovate a building and its facade (or 'envelope') can has considerable advantages. Not only does it improve the quality of life and the performance, it can save energy and increase the building's market value. This makes renovation an interesting proposition for owners, users and architects alike. The facade research group at Delft University of Technology, working with the Dutch facade builders' association VMRG, carried out a three-year research project that yielded a number of basic requests, strategies and practical examples which it then developed together with several enlightened companies. "Reimagining the Envelope" reports on this exchange of ideas between science and practice. The result is a variety of strategies for renovating the envelope and examples of successful projects. It also presents a number of far-reaching design ideas.