One of the most eagerly awaited exhibitions of the summer is this retrospective devoted to the work of Vlado Martek (born 1951), one of Croatia’s most inventive and mercurial artist-provocateurs. A poet, painter, graphic artist and occasional performance artist, Martek creates images that look simple but which stay in the memory a lot longer than you expect. His most famous work is a map of America with the word “Balkan”scrawled across it – the kind of throwaway joke that you end up spending ages thinking about. Martek’s mixture of warmth, humour and subversion has been an inspiration to many others, and it is no surprise that his work has become something of a Croatian classic, a running commentary on the absurdities of the age.