There is a long-standing, though contested, argument that in Westminster-style systems parliaments are in decline. The frequency with which the head of government intervenes in parliament is one indicator of this supposed decline. Studies conducted in Britain and Canada show that the frequency of prime ministerial interventions has declined over time, suggesting that the decline of parliament thesis holds true in this regard at least. This article examines the Irish case and shows that the situation is different. As in Britain and Canada, there has been a decline in particular forms of activity (giving speeches and making minor interventions). However, the overall level of prime ministerial activity in Ireland has increased over time. These findings suggest that in the Irish case at least and on the basis of this one indicator the decline of parliament thesis does not hold true. Moreover, when we contextualise the findings, particularly on the basis of a qualitative analysis of the changing nature of the presentation of the Order of Business over the last 30 years, we find that the decline of parliament thesis is weakened further. Thus, this paper suggests that the decline of parliament thesis is not applicable to all examples of Westminster-like parliamentary systems. It also indicates that further research on this topic needs to contextualise the changing nature of the relationship between the head of government and the legislature very carefully.