Thai politics during General Prem Tinsulanonda period could be regarded as a transition to democracy of Thailand. Although Thai political economy structure was adjusted in 1980s, this structure did not truly change power structure in the Thai society. This thesis examined the Thai politics under structure of semi-democratic regime during this period and analyzed how General Prem managed to remain in power for eight years. It employed historical institutionalism as well as state-society relations and structuralism as analytical framework. It found that General Prem’s political management under this structure strengthened Thai bureaucratic state through the creation of the networks of authoritarian military-technocratic alliance and non-bureaucratic group (politician and business groups) in policy making process to make a more open bureaucratic polity. Sparing no serious attempt to build a long-term development towards a full democracy, he solidified his political power through the support from mechanism of bureaucratic polity and through the promotions of royal patron-client value in Thai society. He was also able to manage the political forces for political stability, which in turn increased the state capacity to deal with a host of economic and security-problems of the country. By adjusting and augmenting institutional roles of the army, technocrats, politicians and business groups and by balancing power of political actors with the support from the monarchy, he could consolidate his hegemonic grip on power, thereby making him the longest parliamentary premiership in Thai history
