Background/Context The Adult School of La Verneda-Sant Martí, located in Barcelona, Spain, is a reference at the international level because of its trajectory and its contributions to the transformative movement in democratic education. The school was created in 1978 to address the demands of the La Verneda neighborhood's working-class residents, who needed an adult school that could reverse the lack of academic education of neighborhood adults. This school builds on the precedents of popular education developed by the libertarian movement prior to the Franco dictatorship. Since its beginnings, the school has continuously taught people to read and write, helping adults obtain academic degrees that facilitated their labor insertion or promoted their access to university. The school's success is confirmed by the current data: It has approximately 2,000 participants, 5 workers, and 150 volunteers. The key to its success is an effective democratic organization and functioning as well as broad development of activities and an accessible schedule—the school is open Monday through Sunday, from 9 a.m. until 10 p.m.—that meets the real needs of neighborhood residents. The adult participants, together with the teachers and the volunteers, determine and organize the activities that will be conducted in the school. Purpose This article analyzes the democratic organization of this school and its relation to libertarian education in the early 20th century in Spain to investigate two research questions. First, what type of democratic organization and functioning is contributing to increasing the educational level and skills of nonacademic adults? Second, how does this organization contribute to the improvement of the quality of life achieved through the La Verneda neighborhood's movement? Research Design The article reviews the literature on libertarian education in Spain and addresses the Adult School of La Verneda-Sant Martí and Schools as Learning Communities. Additionally, other documents related to the history, activities, and functioning of this school and different types of documents about the neighborhood in which it is located are analyzed. Interviews with participants (this is how adult learners refer to themselves) and communicative observations in classrooms, assemblies, and meetings during the 2012–2013 school year were conducted to contrast with the information found in the internal documents of the school. Findings/Results Besides the documents found on the School foundation that made explicit the libertarian educational ideals, the study identified these principles in the whole evolution and success of the Adult School until the current time. Particularly, we identified three main results: (1) nonacademic adults take part in all of the decision-making processes; therefore, all activities reflect their interests and needs, increasing their educational level and skills; (2) the school is open to the community and has engaged many diverse people as volunteers who contribute to a broad and high-quality education; and (3) the democratic organization of libertarian origins has influence beyond the School walls: a neighborhood movement to improve the quality of life and the transformation of children's schools into Learning Communities. Conclusions/Recommendations This article concludes that the principles present in libertarian education in the early 20th century in Spain have been included in the organization and in the education provided by the Adult School of La Verneda-Sant Martí. These principles are contributing to increasing the educational level and skills of nonacademic adults as well as improving the quality of life achieved through the La Verneda neighborhood's movement. Future research should focus on how this school model has been transferred to other schools and how it influenced the work of the teachers.