My research concentrates primarily on Icelandic language and linguistics, the history of the Icelandic language, and language change and variation in Icelandic through the centuries. I have also worked extensively on medieval Icelandic manuscripts as sources of evidence for earlier stages of the Icelandic language, medieval Icelandic manuscript culture, scribal practice, scribal networks, and the transmission of texts from one generation to the next. I have also done research on the Icelandic language in the nineteenth century and the emergence of the modern Icelandic language standard. In addition, I have also been involved in matters of Icelandic language policy.