Ever since 2004 Quacquarelli Symonds (QS) has been publishing World University Rankings. The latter were developed to measure the main things that go on in a university, i.e. teaching and research, using several measures to capture university excellence; these include institutions attractiveness to international students and academic staff, staff/student ratios, citations, and quantitative surveys completed by academics.
The 2011 rankings are now in, and Chiang Mai University occupies slot no. 67 of the universities in Asia. In total 5 universities of Thailand made it to the top 100, and these are:
Chiang Mai 67
Prince of Songkhla 95
The no. 1 slot went to the Hong Kong University of Science and Technology.
Further details can be obtained on www.topuniversities.com, which also gives a breakdown by subject (see link below).