Summary: GAO discussed the Postal Service's (USPS) assignment of mailing addresses that are in a different municipality from their physical location. GAO noted that: (1) numerous complaints from customers and municipalities are made because mailing addresses are used as geographic locators; (2) differences can cause delays in the delivery of emergency services; (3) affected residents can incur increased insurance rates; (4) the practice distorts the allocation of funds to municipalities by state and local governments; and (5) differences could result in improper assessment of wage and sales taxes. GAO also noted that: (1) proposed legislation would lessen the absolute control that USPS has over the designation of mailing addresses; (2) the proposed legislation could be expensive and disruptive to mail delivery services; (3) boundary changes often result in the transfer of deliveries to other carrier routes; and (4) USPS will need additional letter carriers and space to handle additional deliveries resulting from mailing address changes.