Photographs and architectural drawings of Lienau's work, much of it in New York City and in New Jersey. Projects include the Gardner A. Sage Library for the General Theological Seminary in New Brunswick, N.J.; the Francis Cottenet Villa in Dobbs Ferry, N.Y.; a house for Legrand Lockwood in South Norwalk, Conn., later owned by Mark Twain and now known as the Lockwood-Mathews Mansion; and the Telfair Academy of Arts and Sciences in Savannah, Ga. Also included are drawings of unidentified or unexecuted buildings; student drawings, and early European commissions; lecture notes, 1835-1837, from the Stadtische Gewerbeschule, Berlin; a partial list of of Lienau's work, 1848-1886; specifications; acounts; printed material; photographs, postcards, and prints showing various European buildings; clippings; certificates; typescripts of articles; and correspondence.

Architectural drawings and specifications for Codman's projects, circa 1890s-1930s, including the Martha Codman house in Washington, D.C.; alterations for Edith Wharton and her husband at their three residences, the Mount in Lenox, Mass., Land's End in Newport, R.I., and their Park Avenue home in New York City; work for the Thayer family of Boston, Mass., specifically Nathaniel Thayer's three homes in Boston, Lancaster, Mass., and Newport, R.I. ("Edgemere"), Bernard Thayer's Beacon Hill houyse in Boston, and Eugene Van Rensselaer Thayer's two houses in Boston and Lancaster, Mass.; the Lucy Dahlgren house in New York City; the Archer M. Huntington house on Fifth Avenue in New York City; interior design for John D. Rockefeller in his house "Kykuit" at Pocantico Hills, N.Y.; interior design work for the Vanderbilt family including Cornelius Vanderbilt's "Breakers" at Newport, R.I. and Frederick William Vanderbilt's mansion in Hyde Park, N.Y. and his house on Fifth Avenue in New York City; Oliver Ames' mansion at Pride's Crossing, Beverly, Mass., and his house in Boston; and interior decoration and alterations for Codman's own homes in Newport, R.I. and Roslyn, N.Y. and his villa in France, "La Leopolda", at Villefranche-sur-Mer. Also, lists, descriptions, and postcards of French chateaux, with related correspondence, circa 1900s-1930s, relating to Codman's bibliography on the chateaux of France; and miscellaneous lists of houses in England and France, correspondence, and printed material.