Benavides began working for human rights and peace in the 1970s. After the military coup in El Salvador in 1979 and the outbreak of the Salvadoran Civil War, she became the leader of the Ecumenical Committee for Humanitarian Aid, a group sponsored by the Archbishop Óscar Romero. Romero was assassinated in 1980. In 1982 Benavides went into exile in Mexico and the United States, and continued her efforts from there.