The negative impact of worm parasites on livestock animal health/welfare and on plant crop health seriously undermines food production systems and poses a direct threat to global food security. However, the use of chemical products to treat worms is not sustainable in the long term because of the continual emergence of drug-resistant parasites. Also, the presence of chemical and antibiotic residues in food has heightened consumers concerns about how food is produced and what they are eating. Vaccines, on the other hand, are sustainable and the most appropriate way forward; they are safe, leave no chemical residues in food, are environmentally friendly and are acceptable to both users and consumers. However, despite the huge successes we have made in vaccine development against viruses and bacteria over the past 200 years there are presently no vaccines for any animal or human helminth pathogen. Some of the most important farm-level diseases are caused by liver flukes and several species of gastrointestinal worms. Liver fluke disease, or fascioliosis, is a worldwide infection of livestock (especially sheep and cattle) and also an important pathogen of humans. This parasite is considered one of the most successful parasites because it has the greatest geographical and global distribution, and the widest host range of all helminths. The parasite’s success is related to the efficiency by which it invades its host and suppresses protective immune responses. The rapidity and potency by which liver fluke commands the host response makes it an ideal pathogen to study the mechanisms behind helminth immunomodulation, and also for the investigation of new ways of developing anti-helminth vaccines. The global objective of this project is to develop a successful vaccination against liver fluke by blocking the ability of helminth parasites to suppress the immune system in cattle (FLUKVAC).