architect and leader of the school of Amsterdam, which stressed individualism, fantasy, and picturesqueness in its architectural design. De Klerk worked as a draftsman, then studied in Scandinavia, later returning to Amsterdam. His Hille Building (1911) is considered the first example of the Amsterdam school. His most important work was the Eigen Haard Estates (1917–21), which show the whimsy and warm humanity of de Klerk's design, as well as his attention to the quaintness of the Dutch tradition of folk architecture.