Published online by Cambridge University Press: 29 September 2021
This article argues that the impact of veto points on a government's policy outcomes depends crucially on the degree of institutionalization of the party system. Specifically, the article claims that two dimensions of party system institutionalization – stability of relations between parties and between parties and voters – condition the ability of the opposition to block governments' policy plans through veto points. It showcases this argument by applying the method of causal process tracing to a comparative analysis of health policy reforms in Slovakia (2002–2004) and Hungary (2006–2008).