By the time of his mysterious death in 1974, Louis Kahn was widely recognized as one of the greatest architects of his era. Yet this enormous reputation was based on only a handful of masterpieces, all built during the last fifteen years of his life. Rather than focusing on corporate commissions, Kahn devoted himself to designing research facilities, government centers, museums, libraries and other structures that would serve the public good. But this warm, captivating person, beloved by students and admired by colleagues, was also a secret man hiding under a series of masks. Drawing on extensive original research, lengthy interviews with his children, his colleagues, and his students, and travel to the far-flung sites of his career-defining buildings, Wendy Lesser's You Say to Brick is a landmark biography of this elusive genius.