The role of the Institute has developed over the 30 years of its life. CULI carries out research into English as a Foreign Language. It also organizes the national seminars annually and international conferences every four years. It regularly publishes PASAA, the oldest professional language teaching journal in English in Thailand and PASAA PARITAT, an annual publication of the English Language teaching journal in Thai. More recently it has begun providing English instruction for Thai and overseas students who enroll in international courses in Business Studies, Architecture, Engineering, Science, and Communication Arts in which the medium of instruction is English. Its expanded role means that the institute operates all months of the year and often on weekends and in the evenings in order to serve a very large and varied clientele.