Dealignment has been recurrently pointed in the literature as a main driver of the so-called “personalization of politics”. The erosion of cleavage-based voting is argued to have produced a decline in the electoral relevance of long-standing partisan attachments, progressively replaced by short-term factors such as evaluations of party leaders running for election. Yet, on the one hand, the claim that leader effects on voting behaviour have been increasing across time is short on comparative evidence, and on the other hand, there is limited empirical evidence that such increase is due to dealignment. This paper addresses these claims, exploring the longitudinal relationship between dealignment and the personalization of politics through a novel dataset pooling national election survey data from 14 Western European parliamentary democracies in the period 1961-2016. The results suggest that both nay-sayers and followers of the personalization of politics were partially right: leader effects did not increase over time, but their relative importance did. Leaders only came to matter more because their parties came to matter less. Partisan dealignment was the key factor in downplaying the electoral impact of partisan attachments vis-à-vis leaders evaluations over the last decades.