The fourth edition includes substantially updated material for Chapter 14 on the Berlin Republic, as well as a number of amendments throughout the text, reflecting the changing emphases of the historiography over recent years. I have again decided against major restructuring and rewriting, although in many areas, if I were to start afresh, it would be a substantially different book. I would like in particular to thank the following for their helpful written comments on the previous edition, particularly relating to references to Poland throughout the work: Professor Daria Nałęcz of the Polish Academy of Sciences, Lazarski University; Professor Marek Wierzbicki of the Catholic University of Lublin; and Marcin Wodziński of the University of Wrocław; as well as other participants in a meeting on ‘Recovering Forgotten History’ which took place in Warsaw in 2011. I would also like to thank the anonymous readers for Blackwell for their various suggestions regarding the whole text, and Carl for his characteristically perceptive and intelligent comments on aspects of Weimar culture.