RegistryNXT! is a novel, web-based data collection and reporting technology platform that underlies the Sanofi Genzyme Rare Disease Registries. The Rare Disease Registries are a global, observational, and voluntary program designed to collect patient clinical data related to the onset, progression, and treatment course of Gaucher, Fabry, MPS I and Pompe diseases. Publication of these data in peer-reviewed biomedical journals is a major emphasis of the Rare Disease Registries. In addition, such data are used to fulfill various global regulatory commitments of Sanofi Genzyme. Regional and International Advisory Boards provide scientific oversight and direction to the Rare Disease Registries. Advisory Board members are physicians with expertise in the diseases included in the Rare Disease Registries and serve as liaisons between the Rare Disease Registries and the respective medical communities.