The following article suggests a critical realistic framework, which aims at modeling sociotechnical change linked to end-users’ IT appropriation: the “archetypal approach.” The basic situations it includes (the “sociotechnical archetypes”), and the possible appropriative trajectories that combine them, together with three propositions linked to the model, are developed. They are illustrated by means of a case study describing the implementation of an e-learning system within a French university. Then, the article presents an instrumentation of the theoretical framework, based on a quantitative longitudinal approach: the Process Patterns Recognition (PPR) method. This one draws mainly on Doty, Glick and Huber (1993, 1994), who propose to evaluate the distance between organizational archetypes and empirical configurations by means of Euclidean distance calculus. The adaptation consists of evaluating the distance between appropriative trajectories (embodied by series of theoreti-cally specified vectors) and empirical processes linked to the implementation of computerized tools in organizations. The PPR method is then applied to the same organizational setting as the one related to the case study. It validates the relevance of this type of a research strategy, which makes it possible to model sociotechnical dynamics related to end-users’ IT appropriations.