The COSEB kick-off meeting was organized in April 2023, and highlighted the stakeholder perspectives on the unmet and urgent need to work towards reasonable harmonization of outcome measurement in epidermolysis bullosa (EB) by developing core outcome sets for the different EB types. Standardized and uniform outcome assessment holds great promise to reduce selective reporting, improve the comparability and pooling of treatment outcomes, and enhance the efficacy of future research in EB.