This paper first introduces ‘Europeanisation’, a key concept to enable examination of EU influence, policy transfer and convergence. It then outlines the broad parameters of European social policy and historical developments in European social policies, politics and institutions, drawing particular attention to Ireland’s contribution to shaping EU social policy. Thereafter, the article takes a chronological approach to focus on how EU policy and practice shaped the Irish welfare state and public administration of Irish social policy. This article examines four phases of Ireland’s EU membership and asks how Irish social policy was influenced in each of these stages and how Ireland influenced EU social policy. Stage one examines the 1970s to mid-1980s; stage two takes in the mid 1980s to the late 1990s; stage three reviews the late 1990s to 2007; and stage four relates to the post 2007 crisis era. The paper concludes that Irish social policy has been significantly influenced by EU social policy, and overall this influence has been largely positive, but also that Ireland hasin turn influenced EU social policy and this influence has been mixed but also largely positive. Over time, through hard law and softer Europeanisation processes, there has arguably been some convergence in social policy across the EU and the EU has played some part in the modernisation of Irish social policy (O’Donnell, 2001; Adshead, 2005). The conclusion reflects on the future suggesting Ireland should seek to once again influence the EU towards a more progressive social direction.