The relationship between Iran, Syria and Hezbollah and its effect on the Lebanese state is here examined. Divided into five parts the study first tackles Iran’s movements in Lebanese space and their connection to Hezbollah’s evolution. The second part focuses on Syria’s intervention in Lebanon and on Hezbollah as an intervention tool. The third part describes Hezbollah’s relationship with Lebanon since the party’s creation as well as the Taif Agreement and the subsequent change in the foundations of that relationship. The fourth part sheds light on the intervention of Iran and Syria in the relationship between Hezbollah and the Lebanese state. Finally, the fifth part explores Hezbollah’s intervention in the Syrian crisis and its repercussions on Lebanon.