Political parties often employ the rhetoric of electoral mandates, claiming that the people who voted for them endorsed their policies. However, the level of voter-party issue congruence may vary across parties, issues, and elections; and the views of certain types of voters may be better represented by their party than others. This paper puts forward a series of hypotheses to explain variation in issue congruence, relating to how well-informed voters are about party policy, the role of non-policy determinants of vote choice, and the nature of policy competition between parties. The hypotheses are tested using data from surveys of voters and parties conducted during the 2020 general election and the 2019 European Parliament election in Ireland. Congruence is found to be higher when a party is particularly associated with an issue. Fianna Fail and Fine Gael, for whom non-policy attributes play a significant part in voters' assessments, are found to have lower policy congruence with their voters overall than other parties. While there is no evidence that certain socio-demographic groups are systematically more or less well represented by their parties across all policy areas, some gaps in representation are identified, particularly in relation to so-called 'cultural' issues.