Ehrenkrantz Eckstut & Kuhn Architects (EE&K) was an internationally recognized architecture firm established in 1959 by Ezra Ehrenkrantz as Building Systems Development. The firm specialized in integrating building design with open spaces to create functional and aesthetically pleasing places. EE&K's expertise encompassed large-scale urban development and infrastructure projects, mixed-use urban development and waterfronts, school and campus design, and historic preservation/adaptive reuse. With offices in New York City, Washington D.C., Los Angeles, and Shanghai, the firm served a diverse clientele ranging from the public sector to academia. In 2011, EE&K merged with Perkins Eastman, another New York-based architecture firm.