In addition to supplementing these old holdings, the collection was greatly expanded in the 1970s through donations of important and extensive estates of contemporary architects. These donations provided the impetus for the founding of the saai. This took place in 1989 following a decision by the state government of Baden-Württemberg. The saai is a service facility of the KIT and is managed by the head of the Department of Architectural Theory.

Since 1989, the collection has been expanded with materials on the work of 20th-century architects, significantly supplementing the old holdings. The saai collects, archives, and preserves the material of significant architects, engineers, architectural historians, photographers, as well as landscape and interior designers, active in southwestern Germany and worldwide. The collection's main focus is the 20th century. Besides studying its collection, the saai is committed to supporting scholars in their ongoing projects. Through its own publications and exhibitions, the centre fulfills its commitments to the culture of building and cultural history.

The saai holds one of the most impressive collections of its type in Germany, consisting of more than 500,000 plans, drawings, and sketches, 600,000 photographs, slides, negatives, and audio and video tapes, 1,100 meters of shelving for files and records, about 900 models and 50 items of furniture, as well as a wide range of monographs and periodicals (400 meters).