ABSTRACT
Our theoretical approach to dynamic situations is in line with the cogni tive engineering perspective (Rasmussen, Pejtersen, & Goodstein, 1994) but takes a stronger (human) cognitive ergonomic orientation. This approach has several commonalities with NDM research:
• The management of a satisfying level of performance instead of the opti mal performance put forward by control theorists. Given the complex ity of the situations with which the human operator is confronted, the
importance of context, and the existence of tolerance margins, the oper ator is managing a trade-off between several factors to result in an ac ceptable performance (Amalberti, 1996).
