NSF’s Division of Arctic Programs has awarded a collaborative grant to the Wisconsin State Herbarium (WIS) and the University of Alaska’s Museum (ALA) in Fairbanks to provide baseline biodiversity inventory data for one of the most important elements of the Arctic biota – lichens. These symbiotic organisms are highly sensitive to environmental change, and have been used for decades as bioindicators to monitor air pollution, including fluctuating levels of sulfur dioxide and even radioactive isotopes. Their past, current, and future patterns of distribution in Arctic and Subarctic ecosystems are likely to be reflective of significant ecosystem change in temperature, water and nutrient cycling, as well as population dynamics of migratory animals such as caribou. Most of the data concerning current and historical distributions of Arctic lichens presently resides in the literature and within the large natural history collections of North America. These data are generally overlooked, underappreciated, and rarely accessed by the ecologists, conservationists, climatologists, and wildlife biologists who need them most. We are converting these data into electronic format in order to make them readily and freely available to all through the use of powerful biodiversity-informatics tools. Two of the largest collections of Arctic lichens reside in the herbaria of the University of Alaska Museum in Fairbanks, which is estimated to hold >20,000 Arctic lichens within its collection of 0.2 million specimens, and the University of Wisconsin State Herbarium in Madison, which curates >53,000 Arctic lichens within its collection of 1.2 million specimens. The lichens of this latter collection were amassed over 40 years by Dr. J.W. Thomson (1913-2009) who devoted his career at WIS to Arctic lichenology. That dedication culminated in the publication of three voluminous publications on the taxonomy of American Arctic lichens, a portion of which is now out-of-date. Together we are identifying specimens, updating nomenclature, barcoding, georeferencing, and databasing this pair of world-class collections. At the same time, an updated checklist of all Arctic & Subarctic lichen species has been generated, photographs and illustrations digitized, and taxonomic characters for each species coded for use in the creation of dynamic taxonomic keys and species descriptions. Together, this massive set of data is being integrated using the Symbiota software package to generate an online virtual Flora of Arctic Lichens that can be accessed on the web at http://lichenportal.org.