The concept of clusters promises to be a winning solution for regions wanting a slice of the cake in new technological fields. In the textbook it all seems very simple. Take a region, throw in scientists and venture capital, then just wait for success. In reality though, it proves quite different - and difficult. In this article, the authors take a closer look at the four biotech clusters of Berlin, Massachusetts, Paris and Singapore. The authors explore what governments have done in each, the successes so far and the lessons to be drawn for executives.