This collection primarily contains architectural drawings, photographs, business records and reference materials related to the projects and designs of architectural and engineering firm Abbott, Merkt and Company. A subsidiary portion of the collection includes drawings, photographs and papers related to the life and career of Richard H. Tatlow, III, president of Abbott Merkt, as well as the firms and agencies for which he also worked.

This large collection documents in great detail the architectural projects of Abraham Geller and his colleagues throughout the United States and abroad, spanning the 1940s through the 1990s. Types of projects represented include retirement homes, recreational facilities, medical centers, private residences and prototype dwellings for large residential developments, urban renewal projects, and offices.

Architectural drawings for buildings designed by Hamlin including proposed alterations for the Charles Dudley Warner House, circa 1885; pumping station Clear Stream (or Clear Stream Station), Long Island, 1886; American Classical School, Athens, Greece, 1886-1888; proposed cottage for Mrs. R. Hoe at Sea Cliff, Long Island, 1887; an addition to Clinton Hall at Blair Presbyterian Academy, Blairstown, New Jersey, circa 1896; Soldier's Monument, Whitinsville, Massachusetts, circa 1904 (Hamlin was the architect and Herman A. MacNeil was the sculptor); and miscellaneous and unidentified structures. Also included are drawings done by Hamlin while a student at the Massachusetts Institute of Technology, 1876-1877; sketches done by Hamlin on travels both in the United States and abroad, 1867-1923; photographs of various unidentified buildings and architectural drawings; manuscripts of "ARCHITECTURAL SHADES AND SHADOWS" with related drawings"History of American Art" (unfinished, in French), circa 1923, and "MODERN ARCHITECTURE AND THE CRITICS" circa 1923. Personal materials included undated photographs of A.D.F. Hamlin; a photograph of an 1835 portrait of Cyrus Hamlin; a volume containing condolences, 1926, on the occasion of A.D.F. Hamlin's death; and a scrapbook"Memoirs of Amherst, Class of '75" containing programs, invitations, clippings, notes, essays, exam questions, steamship passenger lists, and other materials.

Alan Burnham (1913–1984) was an American architect and architectural historian who served as the Executive Director of the New York City Landmarks Preservation Commission from 1965 to 1973 as well as the Commission's Director of Research. This collection consists mainly of reference materials related to architectural history and New York City architectural history, as well as professional papers and papers relating to Richard Morris Hunt and the history of New York City apartment buildings.

Also, biographical manuscripts, illustrations of coats of arms, pedigree, and lists of his drawings and his library, to circa 1900, much of it done by Joseph B. Davis.

Alexander McMillan Welch (1869-1943) was a New York City based architect who practiced independently and as a member of Welch, Smith & Provot. His firm was best known for designing New York City townhouses in the Beaux-Arts style. The collection includes 1,641 architectural drawings, 196 student drawings, 14 student notebooks, 99 loose photographs and 3 photo albums of project photography, project specifications and files, and some professional ephemera.

Architectural plans and renderings of Welch's designs, largely New York City residences, circa 1890s-1920s; specifications; photographs; and brochures advertising buildings at 787 Fifth Ave., 628 Fifth Ave., and 71 and 73 Murray Street, in New York City. Drawings and a sketchbook done by Welch while a student; fourteen notebooks containing Welch's notes from Columbia classes in architecture, 1888-1890; licenses to practice in New York and New Jersey, 1904-1923; a certificate, 1937, and related correspondence relating to Welch's appointment as a U.S. delegate to the fourteenth International Congress of Architects, held in Paris, July 18-25, 1937. A list of U.S. delegates is included. Of note are drawings and papers for the restoration of the Dyckman House, an 18th century farmhouse in upper Manhattan (1910-1917); and the Mrs. Rutherford Stuyvesant Estate in Allamuchy, New Jersey, and the Rutherford Stuyvesant Momument in Tranquility Cemetery, Tranquility, New Jersey, designed by sculptor Daniel Chester French.

Angelo Monaco (CC '87) studied architecture as an undergraduate at Columbia University. Included in this small collection is a 1-page reminiscence on Douglas Darden who was a studio critic while Monaco was an architecture student (2016); a pencil, color pencil, and ink sketch by Darden titled "The Three Temptations" drawn on the verso of a floor plan of Avery Hall's Wood Auditorium (1985); and a signed 10-page lecture "The Diagram as a Space of Difference" by Peter Eisenman (2005).

The materials that comprise the Vertical File have been collected and added to from a variety of sources by former Avery Librarians. The vertical file contains clippings, pamphlets, reprints, and other miscellaneous materials relating to persons, places, organizations, and topical subjects relating to architecture, housing, and city planning. The purpose of the vertical file was to arrange and store small items, memorabilia, and ephemeral material on a variety of topics to facilitate access by researchers. For the most part, the vertical file contains printed items only. Manuscript material and other unique items were, generally, not placed in the vertical file. In some cases, manuscript material has been removed from the Vertical File and placed in its corresponding collection.

Three sketchbooks; the first, 1893-1894, containing sketches from his student years at the Columbia School of Mines, Department of Architecture (he received his degree in 1894); the second, 1894-1896, containing sketches made as a student at the Ecole des Beaux-Arts in Paris; and the third, circa 1896-circa 1905, containing sketches for a variety of projects and designs. Buildings and other structures depicted include the Academy of Music on 14th Street, New York City (a seating plan); Wells Fargo Bank Building, Portland, Oregon, 1910; Reunion Hall, Princeton University, 1902; lantern for the Aetna Building, Hartford, Connecticut; Woodland Street entrance to Kinney Park, Hartford, Connecticut, 1905 (some drawings are by others). Program notes from the classes of Paul Blondel and J. Gaudet at the Ecole des Beaux Arts are included. Also, designs (some done in partnership with Joseph Urban) for proposals for the Metropolitan Opera Company on various sites in New York City, circa 1920s; and designs for shopping and music centers in New York City, to 1936.