Alexander Stewart Walker (1906-1945) and Leon Narcisse Gillette (1878-1945) were first employed by the Coes to build a new house at their Wyoming ranch in 1911. The firm was then commissioned to design several outbuildings for Planting Fields circa 1916. The Haybarn, Dairy, Carriage House and Laundry were all designed with lamay brick and steeply pitched slate roofs in a style that matched the Queen Anne Style Byrne mansion. When that house burned down, the Coes wasted little time in commissioning Walker and Gillette to design a new house for the estate, what we now know as Coe Hall The firm also worked with the Coes' landscape architects to design some of the features around Coe Hall, like the Surprise Pool which was a collaboration with Lowell & Sargent. As well, Walker and Gillette designed some of the reproduction Elizabethan furniture the Coes had made for the new house, including Mr. Coe's Tester bed and the Dining Room table Walker & Gillette designed 12 country homes on Long Island, the first in 1910 and the last in 1940, as well as The Creek Club in Lattingtown (1923). The firm's residential designs on Long Island range from Tudor Revival to Stick Style.