Thailand is now engaged in the important process of reforming the country's telecommunications structure. New telecommunications acts have been passed and regulators have been designated to regulate this telecommunications transformation. However, there are many critical details that must be determined. This thesis aims to identify appropriate universal service mechanisms for Thailand. It focuses on universal service with regard to telecommunication regulatory policies for fixed telephone services. This study uses a qualitative analysis of multiple case comparisons as the methodology for exploring the universal service mechanisms in five countries: the United States of America, the United Kingdom, Chile, Peru and Malaysia. Each of these countries was selected after consideration of the telecommunications mechanisms they have implemented, as well as for key criteria that typically should be considered when choosing universal service mechanisms. After considering the key criteria with regard to characteristics of telecommunications in Thailand, this thesis concludes that the appropriate universal service mechanism for the country is a hybrid scheme that employs both Mandatory Service Obligations (MSOs) and Auctions through the Universal Service Fund (USF). The application of MSOs has been chosen to ensure that telecommunications providers fulfill their universal service obligations, while auction has been chosen in compliance with the USF. The recommendations from this thesis can serve as guidelines for universal service for telecommunications regulatory policies of Thailand. Nevertheless, additional specific details of implementation should be considered and other comprehensive methodologies should be conducted in order to increase the ability to generalize these results.