On the one hand, 24 countries with a closed-list system have been analysed. They can be divided between nationwide and multi-member proportional systems. On the other hand, in the open-list systems, the seat allocation within candidate lists can be done in many ways. While seven countries use one-preference systems (Austria, Denmark, Estonia, Finland, the Netherlands, Poland and Sweden), many other countries use several-preference systems. In this last category, seven countries have a fixed number of preferences (Cyprus, Czech Republic, Greece, Kosovo, Lithuania, Peru and Slovakia) whereas ten countries have a variable number of preferences, depending on the number of seats to allocate in the constituency (Armenia, Belgium, Bosnia and Herzegovina, Brazil, Bulgaria, Iceland, Kyrgyzstan, Latvia, Norway and San Marino).