The Dutch Parliamentary Election Studies (DPES) are a series of national surveys carried out under the auspices of the Dutch Electoral Research Foundation (SKON). These surveys have been conducted since 1970. Many questions are replicated across studies, although each has questions not asked in the others. The major substantive areas consistently covered include the respondents' attitudes toward and expectations of the government and its effectiveness in both domestic and foreign policy, the most important problems facing the people of the Netherlands, the respondents' voting behavior and participation history, and his/her knowledge of and faith in the nation's political leaders.
In Dutch: Nationaal kiezersonderzoek (NKO) http://www.dpes.nl/nl/