In less than two decades, Jacoba van Heemskerck (1876-1923) created a powerful oeuvre comprising paintings, woodcuts, glass works and mosaics. Her expressive subjects, including landscapes, townscapes and harbour scenes, are characterised by luminosity and increasing transparency, by rhythmical compositions of the pictorial space, black contours and an intensive use of colour. After her artistic beginnings in the circle around Mondrian and elsewhere, Jacoba van Heemskerck belonged to the centre of the avant-garde movement emanating from the "Sturm" of Herwarth Walden in Berlin - the gallerist and publisher who made artists like Marc, Kandinsky and Jawlensky famous. Her work is shaped by her orientation towards Anthroposophy, which bears witness to her interest in the elemental effect of light and colour on the viewer. Her creative work is highly topical today thanks to her understanding of nature and the cosmos as a world viewed as a whole.