Biological control is an important tool in managing noxious weed invasions in western Forests. Many of these weeds are particularly invasive following fire and compete with natural plant communities. We initiated new studies with support from the Fire Plan. We work with many cooperators in Eurasia, including Switzerland, France, Republic of Georgia, Bulgaria and Ukraine to understand the natural history of weeds and to search for biological control. A Bulgarian graduate student is studying the natural enemies of Rush skeletonweed in that part of its home range. We evaluate the host specificity and effectiveness of the agents in quarantine before releasing and monitoring them in the field. In Switzerland, we are studying the biology and learning how to propagate a root- feeding beetle for tansy ragwort. These colonies are being evaluated in quarantine. Typically, a complex of agents attacking different plant organs (flowering parts, stems, roots) is necessary for effective control. In NW Montana, we are assessing such a complex affecting tansy ragwort populations.