The Hurler-Scheie phenotype in a 27-year-old woman of first-cousin parentage is possibly the first reported in the orthopedic literature. The patient exhibited short stature, coarse facies, corneal clouding, multiple stiff joints, normal intelligence, and a long history of bilateral carpal tunnel syndrome, which has not been relieved after operation. The irreversible nerve damage was apparently produced by the marked thickening of the transverse carpal ligament. Surgical findings in this case and data from published reports emphasize the need for early surgical treatment of the associated carpal tunnel syndrome in patients with the Hurler-Scheie phenotype. Parental consanguinity present in this patient is further evidence supporting the concept of a third mutant allele different from both the Hurler gene and the Scheie gene.