Although officially barred from West Germany (and several other countries at various times, including the United States, France, Switzerland, and Australia), he gained a PhD from the Free University of Berlin in 1972 (where he taught some months), published as Late Capitalism, and he subsequently gained a lecturer position at the Free University of Brussels. In 1978 he delivered the Alfred Marshall Lectures at the University of Cambridge, on the topic of the long waves of capitalist development.