This article puts forward a way to study the dynamics of an emergency event. Our focus is on the dynamics of human collective activities during emergency periods and on their relations with the occurrence of crises. Distinguishing three dimensions for the analyses, a complex but rich framework is presented. The various theories on collective work (situated action, distributed cognition, interactionism, workplace studies) constitute interesting bases to start an accurate and complete analysis of collective actions in complex situations. The analysis of emergencies on the basis of these perspectives is a challenge for future research in this field.