1. Introduction: the story of Varieties of Democracy Michael Coppedge, Staffan I. Lindberg and Carl Henrik Knutsen; 2. Conceptual scheme John Gerring, Svend-Erik Skaaning, David Altman, Michael Bernhard, Michael Coppedge, Carl-Henrik Knutsen, Staffan I. Lindberg, Kelly McMann and Jan Teorell; 3. Data collection Staffan I. Lindberg, Valeriya Mechkova, Natalia Stepanova, Jan Teorell, Michael Coppedge and Carl Henrik Knutsen; 4. The measurement model and reliability Daniel Pemstein, Kyle Marquardt, Brigitte Seim, Eitan Tzelgov, Yi-ting Wang and Farhad Miri; 5. Dimensions and components of democracy Jan Teorell; 6. Data validation Brigitte Seim, Michael Bernhard, Fernando Bizzarro Neto, Michael Coppedge, John Gerring, Staffan I. Lindberg, Matthew Maguire, Daniel Pemstein, Jan Teorell and Eitan Tzelgov; 7. Explanatory analysis with Varieties of Democracy data Michael Coppedge, Adam Glynn, Carl Henrik Knutsen and Daniel Pemstein.