This article studies the extent to which Dutch political parties fulfil their electoral mandates. The central question is how collective mandate fulfilment has developed over the last sixty years. Increasing electoral volatility, changes in party organizations and the rise of populist parties could have resulted in a decrease of party mandate fulfilment. Contrary to previous studies, this article studies the mandate in terms of congruence between the electoral and parliamentary party competition. This allows for the study of opposition parties’ mandate fulfilment. Election manifestos and parliamentary debates are studied for six elections and the subsequent parliaments (between 1950-2006). The structure of the party competition is rather congruent before and after elections for all of the cases, except 1972-1977. There is no evidence for a decline of the degree to which parties collectively fulfil their electoral mandates.