Despite the seismic shift of Sinn Féin from being the ‘mouthpiece’ of the Provisional IRA to the largest nationalist force in Northern Ireland, the party continues to project its objectives within the revolutionary politics and tradition of 1916. Whilst various groups across the island of Ireland stress their loyalty to Irish independence and allegiance to their republican forefathers, 2016 also plays host to devolved assembly elections in Northern Ireland. The centenary of the Easter Rising is therefore a poignant moment to reassess republican politics, more specifically, the relationship between the armed revolutionary tradition and constitutionalism. Within the post-peace process era Sinn Féin have been accused of maintaining an autocratic culture and an intra-party framework that is more representative of a clandestine revolutionary organisation than a political party. Yet, simultaneously, Sinn Féin have not been immune to the pressures experienced by other modern political parties, bound by the laws of electoral competition and driven by office seeking priorities. In order to explore Sinn Féin within the modern political arena this paper firstly examines the broader debate surrounding how armed groups make the transition into constitutional politics. Secondly, public opinion survey data is used to judge the basis of Sinn Féin’s electoral appeal. Finally, internal party documents are used to examine party structure, intra-party democracy and professionalisation in order to judge the extent to which Sinn Féin have completed the transition from being a ‘mouthpiece’ to their armed counter-part, towards being a ‘normal’ political party.