In the wake of the collapse of the dictatorship in Tunisia, the Tunisian General Labour Union (UGTT) constituted a key player in ensuring the country stayed on track for a peaceful transition to democracy. This article is intended as a guide facilitating better understanding of the UGTT’s power which allowed the trade union to assert itself and serve as a balancing force in a national context marked by strong political competition and significant social instability. In this context, the authors explore the origins of the UGTT’s power and analyse how these power resources were articulated and combined in the national dialogue (between October 2013 and November 2014), a process that allowed the country to extricate itself from the political impasse, earning the UGTT and three other civil society organisations the Nobel Peace prize in 2015