Juvenile localized scleroderma (jLS) is a rare condition that can impair health-related quality of life, especially as it affects other body parts besides the skin. Current outcome measures fail to capture this complexity, limiting our understanding of the full impact of jLS. Recently, measures have been developed specifically for jLS, and there is a critical need for coordinated, international partnerships to ensure their validity. This study builds upon existing collaborations between CARRA investigators and members of the Paediatric Rheumatology European Society (PReS) & Paediatric Rheumatology INternational Trials Organisation (PRINTO) to support three aims; the international validation of the Localized Scleroderma Quality of Life Instrument (patient-reported; specific to jLS), further refine the Total Morbidity Score (clinician-reported), and validate Patient-Reported Outcomes Measurement Information System (patient-reported; general). This study will generate the first international jLS dataset to support the use of multiple outcome measures, both of which can be used for future studies.