Volume IV of Distribution maps of Norwegian vascular plants marks the end of a long-lasting project. It presents distribution maps and explanatory texts for more than 200 taxa of vascular plants with an eastern or northeastern distribution pattern in Norway. All basic information (including herbarium specimens, literature, lists) has been critically evaluated. For each taxon, the earliest records, habitat (ecology), and distribution within Norway are commented upon, and the relationship to distribution patterns in neighboring countries is discussed. Although much basic documentation is due to pioneers in the late 18th century and 19th century, substantial new information has been provided during the production of this volume, which also has many comments on solved and unsolved taxonomical problems and problems related to the immigration (or possibly survival) history connected to the taxa. The target audience is botanists dealing with plant taxonomy and phytogeography in boreal and sub