The exit-poll survey of May 21, 1995, the day of the national election, contained after the question of the actual voting behaviour for the Chamber, an open-ended question asking the motives of this voting behaviour. 3547 voters were questioned in the Flemish part of Belgium. Because the exit-poll questioning was done on election day, the voters could not be influenced by the election results and the explanations given by experts in the media. Categorisation of the answers was done by content analysis. The categorisation scheme was developed on the basis of the existing theories of voting behaviour. On this basis an overview is given of the cognitive and affective spontaneous motives the voters are given for their voting behaviour. The inter rater reliability is very high (Kappa: 0.82). With a HlCLASS analysis a motive profile for every party is developed. The results indicate that party identification in a broad sense is still one of the most important explanations ofvoting behaviour. But they also make clear that the stability in voting behaviour is very unsure for an important group ofvoters. The two sources of instability are short term ad hoc motives and a-politic or anti-politie motives among a still growing group of voters.