To be able to compare the benefits experienced by infants with globoid cell leukodystrophy, who receive a possible future treatment, to those untreated, a better understanding of the natural course of infantile GLD is necessary. The current literature contains only case studies of individual or small groups of GLD patients. A longitudinal study of a larger population of patients with infantile GLD has yet to be performed. This protocol is a 1.5 years longitudinal observational study to capture natural history data in patients with infantile GLD. This data will provide information on the range and diversity of clinical disease parameters that can in the future be used to evaluate treatment effects.