Abstract A fragile outsider stance of ''opt-out opt-in'' post-Lisbon now characterizes the Irish relationship with the entire Area of Freedom, Security and Justice, in the form of Protocols and Declarations as contained in the Treaty of Lisbon. The Irish Government commissioned extensive research as to the negative referendum vote on the Treaty of Lisbon in 2008. Importantly, the relationship between public opinion and Irish participation in Justice and Home Affairs, the Area of Freedom, Security and Justice and its opt-out from the Schengen Area did not provoke a negative referendum result according to the research. Water borders and the Common Travel Area shared between Ireland and the UK have had a far-reaching influence on Irish-European affairs. An attempt is made here to trace the influence of British-European relations on the Irish State from the Treaty of Amsterdam to the Treaty of Lisbon and the close ties between the States taking effect in law, policy and even litigation are considered accordingly. The background thereto, in tandem with Irish-specific Protocols and Declarations in the Treaty of Lisbon and the general context of ''Irish(-British) Euro relations'' and EU law, forms the subject of analysis here.