Mucopolysaccharide disorders are rare inborn errors of metabolism (IEM) resulting from a failure in mucopolysaccharide metabolism. They are among a larger group of disorders, all of which involve disordered lysosomal (complex carbohydrate) storage. Each has a specific enzymatic defect and genetic transmission (National MPS Society, 2001). Seven groups of syndromes with overlapping features are currently recognized, several of which have sub- types: Type I: Hurler (MPS IH), Hurler-Scheie (MPS IH/S), and Scheie (MPS IS), ranging from severe to mild, respectively; Type II: Hunter Severe and Mild (MPS IIA and IIB, respectively); Type III: Sanfilippo A-D (MPS IILA-D, respectively); Type IV: Morquio A and B (MPS IVA and IVB, respectively); Type VI: Maroteaux-Lamy Classic Severe, Intermediate, and Mild (MPS VI), Sly (MPS VII), and Diferrante (MPS VIII). Scheie syndrome, previously MPSV, is now classified Type I, leaving the MPSV category empty at this time. Except for Hunter syndrome, which is sex-linked recessive, all MPS disorders are autosomal recessive. All are rare, having individual incidences of about 1 in 100,000 Or lower, but overall MPS incidence is about 1 in 25,000 (National MPS Society, 2001).