Wirtz International, the master landscape architecture firm, originated in 1950 when Jacques Wirtz founded his practice in Schoten, Belgium. The company has since become a thriving family business, with Wirtz's two sons, Martin and Peter, joining the firm, which now employs 11 people. Gardens in Belgium and all its neighboring countries, plus Italy, Switzerland and the United States, are currently underway; past work has been undertaken in Japan, Spain, and Portugal. The company's private projects reach from small courtyards to large estates, corporate headquarters, business parks, and housing developments; public projects consist of parks, boulevards, city squares, university campuses, museums, and streetscape. The firm's designs always enter into dialogue with the surrounding architecture, either to maintain the spirit of the place or to create an entirely new identity. Interior harmony and balance are of the utmost importance, with much reliance on the endlessly expressive qualities of natural materials. A luxurious, oversize two-volume set, "The Wirtz Gardens" contains a selection of 57 private and public gardens, most of them never before published. Included is recent work like the Ainwick Castle Gardens in the U.K. and the Ernsting's Family Estate in Germany, and older projects like the Philosophy and Letters park in Leuven, Belgium, and the Carrousel Gardens in Paris.