The 'BBB-' Standard & Poor's underlying rating (SPUR) on Harris County Municipal Utility District (MUD) No. 188, Texas' unlimited-tax GO bonds reflects the district's: High debt burden, High property tax base concentration, and High tax rate. Factors that moderate these risks include the district's: Participation in the Houston MSA, boosting wealth and income levels; Healthy reserve levels; and Essentially built-out status of development. Harris County MUD No. 188 is about 26 miles northwest of Houston, Texas' central business district, with easy access throughout the entire MSA. Entirely within Houston's extraterritorial jurisdiction, the district's residents have nearby employment opportunities in information technology, petrochemical, professional services, manufacturing and industrial, and retail. The district is residential in nature with a substantial multifamily development,