Isabel Roberts spent three years in New York City, studying architecture in the atelier Masqueray-Chambers (1899-1901), the first atelier (or studio) in the United States established to teach the practice of architecture along the French lines of the Ecole des Beaux Arts. It was established by Emmanuel Louis Masqueray; architect Walter B. Chambers shared in this enterprise. Located at 123 E. 23rd Street, this was the first wholly independent atelier opened in the United States. Masqueray is best remembered as the architect of the St. Louis Exposition and of the Cathedral of Saint Paul in Saint Paul, Minnesota. Roberts found herself among an impressive roster of future architects who studied with Masqueray, including William Van Alen, who would become the architect of the Chrysler Building. Starting in 1899, Masqueray made a concerted effort to include women among his architectural students and even opened a second atelier especially for women students at 37-40 West 22nd Street in New York. As was said at the time, "...he has unbounded faith in women's ability to succeed in architecture...provided they go about it seriously." While in New York, Roberts lived at 129 West 96th Street.