Paul Krugman is ranked among the most influential academic thinkers in the US and is one of the most widely cited economists in the world. However he is not only a researcher but also lively blogger and famous columnist in the New York Times . His research have been highly appreciated by the Nobel Prize Committee and 2008 he became the Laureate of Nobel Prize in Economic Sciences. The lecture is concentrated on his most known research fields i.e. the new trade theory and new economic geography. Additionally there are also some remarks on his achievements in international monetary economics. In order to show why Krugman’s research meant a breakthrough the emphasis is put on the new assumptions he has introduced into his models and the most remarkable conclusions he has drawn. It also describes briefly the further development in economic science caused by Krugman’s publications and the empirical relevance of his models.