There is no one defining element that makes a house modern, and modernity can be expressed in many ways,” insists Matt Berman, a founding principal of the ELLE DECOR A-List architecture firm Workshop/APD. “Overt modernism is often marked by rational organization, open spaces, clean lines, large windows, and crisp detailing. A modern space is also well edited and warm, and it should surprise and delight you as you move through it