Objective. - To provide physicians with a responsible assessment of the diagnosis and treatment of Gaucher disease. Participants. - A nonfederal, nonadvocate, 14-member panel representing the fields of pediatrics, obstetrics and gynecology, genetics, endocrinology, molecular biology, internal medicine, and biostatistics. In addition, 30 experts in genetics, pediatrics, neurology, obstetrics and gynecology, orthopedics, hematology, genetic counseling, clinical pathology, and epidemiology presented data to the panel and e conference audience of 230 during a 1 1/2 -day public session. Questions and statements from conference attendees were considered during the open session. Closed deliberations by the panel occurred during the remainder of the second day and the morning of the third. Evidence. - The literature was searched through MEDLINE, and an extensive bibliography of references was provided to the panel and the conference audience. Experts prepared abstracts with relevant citations from the literature. Scientific evidence was given precedence over clinical anecdotal experience. Consensus Process. - The panel, answering predefined questions, developed their conclusions based on the scientific evidence presented in open forum and on the scientific literature. The panel composed a draft statement that was read in its entirety and circulated to the experts and the audience for comment. Thereafter, the panel resolved conflicting recommendations and released a revised statement at the end of the conference. The panel finalized the revisions within a few weeks after the conference. Conclusions. - Despite the success of enzyme therapy, treatment is limited by the cost of the agent. This makes it imperative to determine the lowest effective initial and maintenance doses, to define the appropriate clinical indications for treatment, and to establish uniform methods to optimize outcome assessment. The value of treatment for asymptomatic individuals has not been determined. General population screening for affected individuals and for carriers is not appropriate at this time. As a prototype for all rare diseases, the plight of patients with Gaucher disease raises difficult financial and ethical issues, which we as a society must address.