Synonymous with Public Service Commission (PSC). In the United States, each of the 50 states has formed a PUC or PSC to regulated public utilities. In the context of telecommunications, the PUCs regulate incumbent local exchange carriers (ILECs), certify competitive local exchange carriers (CLECs), register interexchange carriers (IXCs), adopt and enforce rules relative to competition, oversee emergency services, administer the universal service fund (USF), and monitor service quality. See also CLEC, ILEC, IXC, LEC, USF, and utility.