Comparative Study of Electoral Systems

The Comparative Study of Electoral Systems (CSES) is a collaborative program of research among election study teams from around the world. Participating countries include a common module of survey questions in their post-election studies.  

The resulting data are deposited along with voting, socio-demographic, district and macro variables. Since 2009, GESIS has joined forces with the CSES secretariat in co-operation with the Center for Political Studies if the University of contribute to the production of high quality, free of charge, public datasets. 

The CSES is composed of three tightly linked parts: First, a common module of public opinion survey questions is included in each participant country's post-election study. These "micro" level data include vote choice, candidate and party evaluations, current and retrospective economic evaluations, evaluation of the electoral system itself, in addition to standardized sociodemographic measures. Second, district level data are reported for each respondent, including electoral returns, turnout, and the number of candidates. Finally, system or "macro" level data report aggregate electoral returns, electoral rules and formulas, and regime characteristics. This design allows researchers to conduct cross-level, as well as cross-national analyses, addressing the effects of electoral institutions on citizens' attitudes and behavior, the presence and nature of social and political cleavages, and the evaluation of democratic institutions across different political regimes. Apart from the 'core' questions, each module covers a specific topic of current research in political science.
The research agenda, questionnaires, and study design are developed by an international committee of leading scholars of electoral politics and political science. The design is implemented in each country by their foremost social scientists.

Module I (1996-2001) - Performance of the System -
focuses on three general themes: the impact of electoral institutions on citizens' political cognition and behavior; the nature of political and social cleavages and alignments; and the evaluation of democratic institution and processes.
Module II (2002-2006) - Representation and Accountability -
addresses the contrast between the view that elections are a mechanism to hold government accountable and the view that they are a means to ensure that citizens' views and interests are properly represented in the democratic process.
Module III (2006-2011) - Meaningful Choices -
investigates the meaningfulness of electoral choices. Accordingly, it focuses on a major aspect of electoral research: the contingency in choice of available options.
Module IV (2011-2016) - Distributional Politics and Social Protection -
main topics are voters' preferences for public policy and the mediating factors of political institutions and voting behavior. Additionally, the module includes questions about voters’ political mobilization. The module covers data from elections between 2011 and 2016.
Module V (2016 – 2021) - Democracy divided? People, Politicians and the Politics of Populism -
focuses on the electorate's attitudes towards political elites, on the one hand, and towards "out-groups", on the other hand. It thus enables research on attitudes and voting behavior in the context of a rise of parties campaigning on anti-establishment messages and in opposition to "out-groups".

The free, integrated dataset, codebooks and further documents are available via GESIS Data Catalogue. Data is accessible as a text file and can be imported into SPSS or STATA software packages via prepared syntax files. The online study catalogue ZACAT offers a simple and extended search within question texts, and an preview of the data via online analysis. Further documents like field questionnaires, erata lists and further backgroundinformation about the CSES can be found on

The CSES is also happy to cite all publications and presentations which make use of the CSES data. If you know any which is missing in the bibliography, please let us know through then online form.

If you would like to get updated information and announcements on behalf of the CSES, you can join its newsletter or follow the project on Twitter or the new CSES Blog.

For further questions on the use of the CSES data, download precedures or documents, send an email to the CSES.