My research is in the field of bryophyte taxonomy, systematics and evolutionary history, an area with a strong tradition in Finland since the 1860s. I have focused on understanding the species diversity and evolutionary relationships of liverworts, the first diverging land plant group with probable origins in the Ordovician. In addition to traditional morphological investigations, I have undertaken research projects using molecular level evidence and bioinformatics tools, as well as interdisciplinary approaches. I have led research projects funded by the Academy of Finland and also by the Ministry of the Environment of Finland. Currently I am investigating patterns of endemism in Southern Hemisphere liverworts, which represent high levels of morphological diversity and endemism and have widely disjunct geographical ranges. I have collected bryophyte material for my research in China, Finland, Sri Lanka, New Zealand and Chile.