Abstract
Parliamentary diplomacy is an emerging path in developing international relations. Although parliaments function mainly as legislative producers and scrutinisers, most national parliaments have foreign affairs committees and departments to conduct diplomatic missions. The Thai Senate is part of the bicameral parliament of Thailand, that is active in legislative scrutiny and in diplomatic activities. However, findings from data collection demonstrate that the Thai Senate is yet to become a prominent diplomatic actor, let alone a solid political institution. The duties of the Senate are limited primarily by the Constitutional framework. Therefore, they are required to perform their duties according to the constitutional framework as well as the institutional framework within the limited period of their term in office. The relations between the institution and its actors, the impact of the country’s governing system and political culture, as well as the organisational structure are all factors that influence the purposes and outcomes of parliamentary diplomatic practice. The supporting evidence reflects the bureaucracy and the semi-democratic political system in Thailand that underlie the values and performance of parliamentary actors, seen through the international diplomatic duties of senators and their facilitators. This research shows that parliamentary diplomacy is another dimension of building and maintaining international relations in the parliament level. Moreover, the research would act as a critical document in pointing out institutional flaws for future improvement, in terms of the institutional structure and the actors’ performance.