Dutch painter and a leading innovator of the geometrical abstract style. Piet Mondrian came into contact with Cubism in Paris after 1911 and became associated with De Stijl in 1917. His pictures, at this period, were characterised by vertical and horizontal lines demarcating rectangles which were painted in primary colours, black, white and grey. This geometry was much used by landscape architects and Piet Mondrian became a profound influence on modernist landscape architecture. Typically, demarcations in paving patterns were formed with lines of bricks and the rectangles infilled with slabs, grass, water or planting. Such designs normally lack the compositional harmony and colour brilliance of Piet Mondrian.