Introduction: Facioscapulohumeral muscular dystrophy (FSHD) is a complex neuromuscular disorder with known genetic cause leading to a range of phenotypes and, invariably, muscle weakness. FSHD is genetically defined by a reduction in D4Z4 repeat array (< 10 repeat units) of chromosome 4q35 and hypomethylation, leading to the aberrant expression of DUX4. Toxic gain of function activity of this transcription factor results in accelerated muscle degeneration/regeneration and replacement by fatty, fibrotic tissue with variability across muscles. While natural history studies in the younger pediatric population are small, varied or to yet be completed in North America, there is urgency to include this population in clinical trials. To address this need, a retrospective natural history study is in progress with a goal of identifying potential pediatric-specific outcomes for evaluation in future interventional trials. Methods: Medical records from those diagnosed younger than age 18 were submitted and reviewed according to an IRB approved protocol. The records were managed by two individuals, with one assigning a deidentified code to each subject and the second collecting data from the records into a single dataset file with patients’ anonymous identification code. Preliminary statistical analyses have been completed in R. Results: Preliminary findings are reported for subjects with age of onset of 4.8 ± 2.5 yrs (mean ± SD) and age of clinical diagnosis of 7.7 ± 4.1 yrs (n=9). Symptoms of facial muscle weakness included decreased eye closure, decreased eye brow elevation and inability to smile or keep air in cheeks for all subjects. While limb muscle weakness was variable, a decline in respiratory function (FEV1 and FVC) was consistent and prominent in all cases. Conclusion: A retrospective natural history study of pediatric cases of FSHD is ongoing to rapidly address the urgent need for outcome measures for clinical trials in this pediatric population.