He won the Nobel Peace Prize in 1987 for his efforts to end the Central American conflicts.
Specifically, Arias is credited with:
* Initiating and promoting the Esquipulas II Peace Plan in 1987, which led to peace negotiations between the governments of Nicaragua, El Salvador, Guatemala, and Honduras, and the rebel groups fighting against them.
* Establishing the Arias Foundation for Peace and Human Progress, dedicated to promoting democracy, peace, and human rights in Latin America.
Arias is a vocal advocate for peace and conflict resolution, and he continues to work on these issues through various initiatives and organizations. He is considered one of the most influential figures in Latin American politics and a champion of peace in the region.