Fasciola hepatica, has become an increasingly common parasite of Swedish ruminants. This is believed to be due to climate change in combination with an increased use of wet marginal pastures. At the same time, it cannot be ruled out that the effect of the anthelmintics (flukicides) used to control the parasite has deteriorated due to development of anthelmintic resistance. Alternative explanations for the increased incidence are that dewormings are carried out at the wrong time or using the wrong dosage. In this project, we will evaluate the effect of albendazole that today is the first choice for deworming against the liver fluke both in sheep and cattle in Sweden. We will also develop methods that will be used in a nationwide survey of the resistance status. The project will be conducted in collaboration between experts at Swedish University of Agricultural Sciences, the Swedish Animal Health Service, and with representatives in sheep and cattle industries.