The common understanding of cooperation is working together with someone, helping someone in a specific activity. Cooperation is a variety of connections between individuals, social groups, or organisations that are created in order to achieve a specific goal (Kożuch, 2007). It is also acknowledged that cooperation is one of the most important skills of the 21st century, in addition to creativity, innovation, critical thinking, problem solving skills, metacognition, ability to make use of information and information and communication technologies, etc. (Suto, 2013). These skills are associated with the future economic prosperity of individuals and nations since they ensure the key qualities required for success in the global skills race (Child, Shaw, 2016). Cooperation as a key skill of the 21st century is considered the most important in project work, it impacts learning and maintaining the acquired knowledge, it allows for: effective distribution of work; including information from many sources of knowledge, perspectives, and experiences; and increased creativity and quality of solutions stimulated by the ideas of other group members (OECD, 2013). Cooperation also allows for increasing the social skills of students, e.g. skills in conflict-solving (Ginsburg-Block et al., 2006). Meanwhile, our research shows that the capability to and ability to cooperate is a "forgotten skill" that is difficult to identify both in didactic practice and in formally recorded artist education programmes. This hinders the possibility of graduates of higher schools of art to pursue a satisfying artistic career and move around the labour market. The research problem we are undertaking concerns gaps in teaching students in the scope of developing their competences for cooperation that higher schools of art have. We want to recognize how deficits and development of this competence at the schools are perceived by persons who manage the schools, their graduates, and employers that hire artists after they graduate. We also want to formulate recommendations for managers of schools whose goal is the development of relational competences and cooperation skills of students of higher schools of art. The paper has been prepared on the basis of studies conducted between 2016 and 2018 in 15 (out of the 19 existing) higher schools of art in Poland. It was assumed that the studied schools of art would form a single case study, as part of which mixed, qualitative scientific methods would be used. We have conducted: Individual interviews with two groups of stakeholders of higher schools of art: graduates (28 in-depth interviews, implemented in 2016); people in charge of higher schools of art (10 in-depth interviews in 2016); Focus interviews with the management staff (rectors, chancellors) of higher schools of art in Poland, conducted in 2016 and 2017; CAWI (Computer Assisted Web Interviewing) surveys, conducted every year between 2016 and 2018 with graduates of higher schools of art (surveys of ca. 2,500 graduates from the years 2012-2017 were analysed).