Introduction: Pharmacists' motivation for Continuing Education (CE) and Continuing Professional Development (CPD) play a pivotal role in the quality of learning outcomes and patient care. Autonomous motivation (AM) - in contrast to controlled motivation (CM) - is associated with deep learning, better learning outcomes, and less likely leads to burnout1. By understanding the dynamics of motivation a CE/CPD system might be designed that ideally fosters AM. Aim: The aim of this study was to follow longitudinal changes in motivation of pharmacists participating in the Dutch CE/CPD-system during a two-year period (2013-2015). Method: AM and CM was measured at three time points (0, 9 and 21 months) using 5-point Likert scales from the Academic Motivation Scale and Relative Autonomous Motivation (RAM) was calculated from the sub-scales1. Latent Growth Modelling was used to analyse the data. Results: AM (3.35 ± 0.55) increased over 21 months (slope = 0.071 ± 0.031 per year), but CM (1.87 ± 0.64) increased more steeply (slope = 0.194 ± 0.035 per year). As a consequence, RAM decreased over time. Traineeship was the only factor, which significantly influenced the change in motivation. No subgroups with different developmental trajectories could be identified. Discussion: The RAM of Dutch pharmacists for CE decreased over a 21-month period as a result of a relatively strong increase of CM. Further research is needed to gain a better understanding of the association between pharmacists' motivation and the characteristics of the current CE system.