Abstract Background Uniform and standardized quality indicator (QI) measurement allows to assess quality of care (QoC) and set up quality improvement initiatives. To date there is no uniform measurement of QoC in IBD centres in Belgium. We therefore aimed to adapt existing standards of QoC to practical local needs, and to define a core set of quality measurements (QM) through a multi-stakeholder consensus. Methods A Core Team (4 IBD expert clinicians, 3 researchers) prepared and coordinated the Delphi process (Figure). Through a literature review, 221 existing QIs for IBD were identified. Second, an importance rating scale exercise was performed, leading to 58 QIs that were reformulated into practical QMs. Next, a variety of experts from different centres in Flanders were invited to rate the importance of these 58 QMs on a 10-point Likert scale. In between two consecutive online voting rounds, expert and patient (n=93) perspectives were provided. Furthermore, participants could also suggest items that were missing in the pre-selected list. A consensus threshold of ≥80% of the participants scoring the item 7, 8, 9 or 10 in voting round 2 was applied as the cut-off criterion for an item to be directly included in the final set of QMs. Newly suggested items and items that did not reach the cut-off criterion were discussed and reconsidered for inclusion in the final set during a closing consensus meeting. In order to come to a workable selection of items, participants to the consensus meeting were requested to estimate the potential for improvement of each of the selected QMs. Results In total 40 stakeholders of which 29 IBD clinicians, 7 IBD nurses, 2 paediatricians, 1 abdominal surgeon and 1 chief medical officer from 24 different Flemish centres participated in both Delphi voting rounds. Of this group, 21 IBD clinicians, 3 IBD nurses and 2 paediatricians also participated in the virtual consensus meeting. In total, 50 items reached the cut-off criterion for direct inclusion in the final QM set, the other 8 items and also 3 new items were discussed and re-voted during the consensus meeting of which 8 additionally reached the cut-off criterion to include in the final set. Based on the estimated improvement potential, 19 of these 58 QMs were prioritized and agreed to measure in clinical practice (Table). Conclusion We defined a core set of 58 QMs for IBD based on multi-stakeholder consensus. In the next phase of this project, a more condensed subset of 19 QMs with potential for improvement will be measured in IBD centres across Belgium, allowing QoC assessment, benchmarking and quality improvement initiatives.