The present research develops a formal mathematical model to measure individual motivation at work. Its mathematical specifications correspond to a formal translation of Conservation of Resources (COR) theory core assumptions. It explores how such COR constructs as resource caravan and resource passageway determine patterns of motivational processes. The model is applied to a sample of working professionals (n= 8) from different occupations. Data is obtained from a 5-item Lickert-scale questionnaire based on the COR-Evaluation (COR-E) instrument developed by Hobfoll et al. (1992). Results are presented in the form of eight different Tables that correspond to eight different resource caravans. They unveil how individual motivational processes vary by the extent to which resources interact with an underlying drive for preservation. The role of context is also confirmed as a resource passageway. With regard to methodology, this research emphasizes how measurement based on mathematical modeling can be an alternative to standard data-analytic statistics. At a theory level, it enriches both COR-based literature and theory of workplace motivation. Practically, it provides an analytical instrument that details information on those processes that shape individual motivational profiles in organizations. (Joint with JPascal Bégout)