In the past three decades, Echinococcus multilocularis, the cause of human alveolar echinococcosis, has been reported in several new countries both in definitive hosts (canids) as well as in people. Unless treated, infection with this cestode in people is fatal. In previously endemic countries throughout the Northern Hemisphere, geographic ranges and human and animal prevalence levels seem to be increasing. Anthropogenic influences, including increased globalisation of animals and animal products, and altered human/animal interfaces are thought to play a vital role in the global emergence of this pathogenic cestode. Molecular epidemiological techniques are a useful tool for detecting and tracing introductions, and differentiating these from range expansions.