Conor J. Kelly is the Bingham Fellow in Constitutional Studies at Balliol College, University of Oxford, UK.

"The material is extremely timely and the book can be a reference point to all scholars, politicians and students, who are interested in shaping the constitutional future of these islands."Giada Lagana, Cardiff University, UK"Well-written, well-organised, and empirically rich, as well as theoretically engaging."Tim Bale, Queen Mary, University of London, UK"This is an impressive book that is highly original empirically, covering new ground on party development and change in relation to the EU. It is novel theoretically in challenging the idea that traditional cleavages based on socio-economic, religious, or centre-periphery faultlines can explain the approaches of the parties towards Europe. Instead, multi-level historical institutionalism, based largely upon the variety of political institutions in which those parties sit (and interact with others) offers a more fruitful exploration of party behaviour."Jon Tonge, University of Liverpool, UK

• 1. Introduction 2. Approaches to Understanding Party Behaviour 3. History of the Parties' European Positions (1973-2019) 4. Explaining Sinn Féin's EU Position 5. Explaining The Ulster Unionist Party's EU Position 6. Explaining The Democratic Unionist Party's EU Position 7. The Two Approaches After Brexit (2020-2024) 8. Conclusion

Conor J. Kelly is the Bingham Fellow in Constitutional Studies at Balliol College, University of Oxford, UK.

"The material is extremely timely and the book can be a reference point to all scholars, politicians and students, who are interested in shaping the constitutional future of these islands."Giada Lagana, Cardiff University, UK"Well-written, well-organised, and empirically rich, as well as theoretically engaging."Tim Bale, Queen Mary, University of London, UK"This is an impressive book that is highly original empirically, covering new ground on party development and change in relation to the EU. It is novel theoretically in challenging the idea that traditional cleavages based on socio-economic, religious, or centre-periphery faultlines can explain the approaches of the parties towards Europe. Instead, multi-level historical institutionalism, based largely upon the variety of political institutions in which those parties sit (and interact with others) offers a more fruitful exploration of party behaviour."Jon Tonge, University of Liverpool, UK

• 1. Introduction 2. Approaches to Understanding Party Behaviour 3. History of the Parties' European Positions (1973-2019) 4. Explaining Sinn Féin's EU Position 5. Explaining The Ulster Unionist Party's EU Position 6. Explaining The Democratic Unionist Party's EU Position 7. The Two Approaches After Brexit (2020-2024) 8. Conclusion

Conor J. Kelly is the Bingham Fellow in Constitutional Studies at Balliol College, University of Oxford, UK.

"The material is extremely timely and the book can be a reference point to all scholars, politicians and students, who are interested in shaping the constitutional future of these islands."Giada Lagana, Cardiff University, UK"Well-written, well-organised, and empirically rich, as well as theoretically engaging."Tim Bale, Queen Mary, University of London, UK"This is an impressive book that is highly original empirically, covering new ground on party development and change in relation to the EU. It is novel theoretically in challenging the idea that traditional cleavages based on socio-economic, religious, or centre-periphery faultlines can explain the approaches of the parties towards Europe. Instead, multi-level historical institutionalism, based largely upon the variety of political institutions in which those parties sit (and interact with others) offers a more fruitful exploration of party behaviour."Jon Tonge, University of Liverpool, UK

• 1. Introduction 2. Approaches to Understanding Party Behaviour 3. History of the Parties' European Positions (1973-2019) 4. Explaining Sinn Féin's EU Position 5. Explaining The Ulster Unionist Party's EU Position 6. Explaining The Democratic Unionist Party's EU Position 7. The Two Approaches After Brexit (2020-2024) 8. Conclusion