The PARTIREP voter survey is a unique three wave panel data gathering effort, with two waves before the elections of June 2009 (face-to-face and CATI) and one wave after the elections (CATI). It is representative for the adult population of the Walloon and Flemish region of Belgium.

In wave one, a geographically stratified sample of eligible voters in Flanders and Wallonia was drawn from the national registry. The total number of addresses was 4,363, spread out over 240 sampling points. No replacement addresses were used. The selected individuals were then asked to participate in a CAPI interview that would last approximately 45 minutes. The expected net sample size for wave 1 was 2,400 completed interviews. Due to the lower response rate an additional sample of 500 addresses was obtained for the most problematic sampling points. Field work on wave 1 commenced on February 21st, 2009 and ended on May 23rd, 2009. After field work for wave 1 ended, 2,331 completed interviews had been conducted out of 4,831 addresses, a response rate of 48.3 per cent (32 addresses were omitted from the gross sample as no contact information was obtained from the interviewers during the field work period; they were therefore treated as non-contacts).

Those respondents that were successfully contacted in the first wave were asked to participate in two follow up surveys conducted over the telephone (CATI interviews). Of the 2,331 successfully contacted respondents, 2,057 agreed to participate in these additional surveys. Of those 2,057 contacts, 1,845 were successfully contacted in wave 2 - a response rate of 89.6 per cent. Field work for wave 2 ran from Monday, May 25th until Saturday, June 6th 2009. For wave 3, the same set of respondents was again contacted, which resulted in 1698 completed interviews, which is a response rate of 82.1 per cent. The field work for wave 3 ran from Monday, June 22nd until Monday, August 24th.