Together with studies in linguistics, the Institute has initiated research in sociolinguistics (the sociology of language) in Setumaa (1997), Southeast Estonia (1998), Saare County (2001), and historic Mulgimaa (2002). The main objective of these research projects has been to assess the current state of local languages. In order to reveal the factors shaping language use, empirical data concerning vernacular use and adults - local-language competence has been collected in historic cultural regions and analysed. Residents were asked about their patterns of language use, the places it was spoken and typical topics or subject areas that would be discussed in the local language. Language attitudes were correlated with different socio-demographic indicators. Moreover, problems of identity, traditions, phenomena connected to one's origin, lifestyle, etc, were examined to varying degrees in different studies.

In sum, the principles of local language use are more ore less determined by gender, age and level of education. Typically, middle-aged, elderly, less-educated people and men use the local language more frequently than other groups. In addition, researchers believe that language attitudes have probably changed as a result of institutional change. The attitudes have become more tolerant and supportive. Nevertheless, institutional change and its results are possible to evaluate only over longer periods of time. Changes in attitudes do not necessarily imply positive development in language command and skills. Language ability must be evaluated separately.