This article addresses educational challenges posed by the future of work, examining "21st century skills", their conception, assessment, and valorization. It focuses in particular on key soft skill competencies known as the "4Cs": creativity, critical thinking, collaboration, and communication. In a section on each C, we provide an overview of assessment at the level of individual performance, before focusing on the less common assessment of systemic support for the development of the 4Cs that can be measured at the institutional level (i.e., in schools, universities, professional training programs, etc.). We then present the process of official assessment and certification known as "labelization", suggesting it as a solution both for establishing a publicly trusted assessment of the 4Cs and for promoting their cultural valorization. Next, two variations of the "International Institute for Competency Development's 21st Century Skills Framework" are presented. The first of these comprehensive systems allows for the assessment and labelization of the extent to which development of the 4Cs is supported by a formal educational program or institution. The second assesses informal educational or training experiences, such as playing a game. We discuss the overlap between the 4Cs and the challenges of teaching and institutionalizing them, both of which may be assisted by adopting a dynamic interactionist model of the 4Cs-playfully entitled "Crea-Critical-Collab-ication"-for pedagogical and policy-promotion purposes. We conclude by briefly discussing opportunities presented by future research and new technologies such as artificial intelligence and virtual reality.
Keywords: 21st century skills; 4Cs; assessment; certification; collaboration; communication; creativity; critical thinking; education; future of work; games; labelization; soft skills; training.