This session is part of the STEEPNESS project, an initiative of the Swiss Digital Skills Academy. As learning in open environments with varying degrees of social interactions (e.g., Open Educational Resources, Open Educational Practices, Fablabs, Hackathons,) gains traction, the need for assessing learning outcomes for recognition within flexible learning paths becomes of high importance. In this workshop, we would like to explore and discuss assessment and relate it to different levels of learning in open environments on one hand and certification through micro-credentials on the other. To do so, we start by presenting 3 premises, question the validation of prior learning as a potentially interesting case study and end by discussing the role of Openness.