In addition to seeing the break-down of architecture, design and engineering collections by category in the Collections section of this guide, it is also useful to visualize these materials on a timeline.

The Time Period Index here is intended to make it easier for researchers to locate collections from particular historical eras. Collections are listed by category (Primary Archives; Selected Projects; Thematic Collections; Photographer Archives; and Other Collections), then alphabetically in each section, which allows researchers to easily navigate back to the collection they may want to focus on.