Abstract: At the beginning of the 1970s in Spain, after the social opening derived from the economic policies of Franco’s dictatorship in the 1950s, two public, international, and participatory events were organized: the VII International Council of Societies of Industrial Design (ICSID) Congress in Ibiza, in 1971, and the Pamplona Encounters, in 1972. Both events are now important references for understanding the changes in the consideration of public participation by artists, designers, and architects in the region, motivated both by international trends and by their own particular contexts. Both the Ibiza Congress and the Pamplona Encounters encouraged the creation of ephemeral scenarios to debate issues such as the role of art in the community, the social work of the creator, the change in the conception of the public now understood as a co-author. These artistic experiments created “microenvironments” of freedom and participation in a climate of great political tension, thus anticipating the transition to democracy that would occur a few years after the death of dictator Francisco Franco in 1975.