There are reckoned to be up to 7,000 languages spoken around the world. And yet linguistic theories and our understanding of human language are largely based on what we know about European languages. Linguistic typology approaches human language from a genuinely global, comparative perspective. Several hundreds of languages at a time can be compared in typological studies when trying to work out what languages have in common, and how they differ one from the other. This perspective allows for a very different outlook on language than that offered through the examination of the most familiar, dominant languages.

Professor Matti Miestamo has been involved in several international collaborative projects on linguistic typology, such as the World Atlas of Language Structures database, which, as the title suggests, depicts the diversity of languages in the form of maps. He has also been instrumental in making linguistic typology known within the field of linguistics in Finland.

One of Miestamo's main research preoccupations has been the expression of negation in the world's languages. He has been especially interested in the relationship between the negative and the affirmative – how the expression of negation affects clause structure and how it conditions other parts of grammar. Miestamo has recently taken the same approach in examining the expression of the interrogative function.

Another focal point in Miestamo's typological research involves the complexity of languages: how complexity is to be defined, how languages can be compared in terms of complexity, and whether some languages are simpler than others.

Typological research and linguistic diversity are closely connected to the documentation of languages that have not previously been studied, or whose description is insufficient. Only a small portion of the world's languages have been described even at a basic level, and consequently the empirical data on which we base our understanding of human language is simply too restrictive. Since a significant part of the under-researched languages are also endangered, it is clear that there is an urgent need for their documentation. Moreover, the documentation work has great significance for the language communities' efforts to preserve and revitalise their language and culture. Professor Miestamo currently heads a Skolt Saami documentation project funded by the Kone Foundation.