After Playfair's death, his drawings - regarded as valuable academic remains of a leading figure in Edinburgh's Enlightenment - were preserved in the Library of the University of Edinburgh. While the University expressed willingness to accept the drawings, they asked that they should be catalogued. This was quite a task for Playfair's Trustees when they examined the contents of the Playfair house and office at 17 Great Stuart Street in the city's New Town, and so they retained James A. Hamilton, Playfair's clerk, to sort and catalogue the drawings. Over five thousand drawings were eventually presented to the University. However, an almost equal amount of material was rejected as unworthy of presentation and probably included sketch books, preliminary designs and returned presentation drawings, competition designs, specifications and letters. When Playfair's library and picture collection were auctioned (by Nisbet of Hanover Street, Edinburgh) in November 1857, no mention was made of the rejected material. One of the questions for history is, what happened to the material discarded by Hamilton?

Donated to the University of Edinburgh by William Playfair's trustees through J. T. Gibson-Craig. Housed in cases contiguous to the Great Room (1860) and later in Library attics until transferred to the new Library Strong Room in 1967.