The European Higher Education Area (EHEA) has promoted the implementation of a teaching methodology based on competences. Drawing on New Institutional Sociology, the present work aims to identify and improve knowledge concerning the factors which are hindering that change in the Spanish university system. This is investigated using a case study based on a Spanish university which is a pioneer in the implementation of a competence-based curriculum. The results show that factors identified and analysed are conditioning the change and causing a ceremonial adoption of the competence-based system by the teaching staff. The results of the study may be of use as a reference and orientation for educators and administrators as well as for the regulators of those countries integrated within the EHEA. The study may prove useful in the analysis of inertia factors present when designing and implementing the policies and measures necessary to achieve a comprehensive teaching methodology; one which incorporates learning and assessment of competences in a real manner.