Our objective is the design of a Virtual Learning Environment to train a person performing a work activity, to acquire non-technical skills during the experience of a critical situation. While the person’s performance level is due to carefully acquired technical skills, how it is maintained in front of criticality depends on non-technical skills, such as decision-making, situation awareness or stress management. Following previous break downs of the domains ill-defined aspects, we focus in this paper on the design of an approach to evaluate the variation of a learner’s performance in front of learning situations showing varying degrees of criticality, in the domains of driving and midwifery