The most effective and long-standing opposition groups were organized by the mothers of los desaparecidos.

When the Junta seized power in 1976 most Argentine women were homemakers and the disappearance of their children (over 70% of the disappeared were estimated to be 30 or younger, (Comisión Naciónal sobre la Desaparición de Personas 285)) served as a profound disruption in their lives.  When the disappearances began in 1975 and 1976, their mothers visited police stations, government and military buildings, and hospitals looking for clues about what had happened to their children. These women were either turned away or told that their children had left the country on their own or had been kidnapped by leftist subversives.  Unconvinced, many continued to look for clues.

In Buenos Aires, a group of women began to recognize each other as they went from building to building looking for information.  In 1977, fourteen mothers began a collaborative effort to find their children that eventually became Las Madres de Plaza de Mayo (Bouvard 69).

This group met weekly at La Plaza de Mayo, a central Buenos Aires plaza, where they marched silently in a counterclockwise circle to protest the disappearances of their children and demand their return.  Their numbers grew steadily and more and more mothers became involved, they began an international campaign and lobbied the pope, the international community and human rights organizations to intervene. 

A second group, Las Abuelas de Plaza de Mayo consisting of the parents of pregnant disappeared women and the grandparents of disappeared children, also formed in 1977. An estimated 3% of the disappeared were pregnant women, and over 12% of Los Desaparecidos were estimated to be 20 or younger (Comisión Naciónal sobre la Desaparición de Personas 285).  Las Abuelas focused their campaigns on finding disappeared children, particularly those born in CCDs, and returning them to their families.

After the fall of the dictatorship, Las Madres de la Plaza de Mayo and Abuelas de Plaza de Mayo continued to be a political presence, demanding that their children’s torturers be punished and that the truth of what happened to their children be revealed.  In 1986, the group split into two groups, Asociacion de las Madres de la Plaza de Mayo and Linea Fundadora.

Asociación de las Madres de Plaza de Mayo is dedicated to carrying on the work their children started: they pursue human rights and social justice issues.  La Linea Fundadora devotes itself to preserving the memory of their children and bringing their children’s torturers to justice.  The two groups differ in their attitudes towards exhumations of mass graves and their relationship to the post-junta government (bouvard 164).

Abuelas de la Plaza de Mayo continues to be committed to locating the children born in prison.  After the fall of the junta, it was discovered that many of the disappeared children had been adopted by military families.  Abuelas has spearheaded several projects to help children who suspect that they are the children of disappeared women search for their parents.

The continued work of these groups underscores that the story of Los Desaparecidos is both a contentious and unresolved component of Argentine social memory. The search for Los Desaparecidos and their history is an important to the social and political climate in modern Argentina.