The Theodore Pitcairn Family Papers are housed in two locations. The section of the collections that is housed at Swedenborg Library ranges in time from about 1910 to 2000. The collection includes correspondence to and from Theodore as well as his wife and some of his children from various periods in his life. There are even some examples of his schoolwork as a boy and a young man. There is a small amount of material relating to business interests as well as some material relating to the fine arts. Genealogy and life history material from two of his children are included as well, arranged into their own series.
The section of the collection that resides in Glencairn Museum ranges in time from about 1927 to 1992. The collection includes correspondence to and from Theodore regarding the purchase, sale and loan of art objects and his villa in France. There is a small amount of photographic material relating to the construction of his home in Bryn Athyn, PA. The collection is divided between two .5 foot boxes, based on the size of the materials.