In 1940, Acuña founded the Costa Rican branch of the Pan American Round Table and in 1941 was appointed Costa Rica's delegate to the Inter-American Commission of Women, a post which she held for the next 13 years. She sought and won in 1941 further changes to Costa Rican legislation, obtaining amendments allowing women to be judges, magistrates, and mayors; but her drive to establish a juvenile court at that time failed. In 1941 and 1942, she took courses at Columbia University to study juvenile justice systems, as she believed that protection for women and children required integrated international solutions. As part of her research, Acuña traveled throughout the United States, attending hearings and trials in Dallas, Denver, New York, Salt Lake City, and Washington, D.C. She also visited juvenile detention and correction centers and vocational rehabilitation centers for children with behavioral problems. In 1943, she attended a meeting of the Panamanian Ministers of Education at their request, to suggest educational reforms. Later that year, she founded the feminist journal Mujer y hogar (Woman and Home). She returned to Costa Rica to press for women's political equality. Between 1943 and 1947, the women of Liga Feminista Costarricense met with every Congress demanding the right to vote.
