The tremendous increase in migrations and diasporas of human groups in the last decades are not only bringing along challenging issues for society, especially related to the economic and political management of multiculturalism and culturally effective health care, but they are also creating dramatic changes in traditional knowledge, believes and practices (KBP) related to (medicinal) plant use. The contributors to this volume - all internationally recognized scholars in the field of ethnobiology, transcultural pharmacy, and medical anthropology - analyze these dynamics of traditional knowledge in especially 22 selected case studies. Andrea Pieroni is a Lecturer in Pharmacognosy, Herbal / Traditional Medicines and Ethnopharmacy at the School of Pharmacy at the University of Bradford, UK. He holds a Ph.D. in Pharmacy from the University of Bonn. His recent research concerns transcultural health and pharmacy, traditional medicines and ethnobotany. He is the Editor-in-Chief of the new Journal of Ethnobiology and Ethnomedicine and the coordinator of the first collaborative ethnobotanical research project funded by the EU Commission (RUBIA). Ina Vandebroek is a post-doctoral research associate at the Institute of Economic Botany, New York Botanical Garden, USA. She holds a Ph.D. in neurospychopharmacology from the University of Ghent, Belgium, and has conducted research into the ethnobotany and ethnomedicine of traditional healers in the Bolivian Andes and Amazon. The project she is currently working on at the New York Botanical Gardens is funded by the National Institutes of Health and involves the dynamics of medicinal plant knowledge and use by Dominican immigrants in New York City.