The GroupHouseNet aim is to provide the European livestock industry with innovations in breeding and management for pigs and poultry that are needed for a successful transition to large group housing systems without necessitating painful tail docking and beak trimming. Allowing the animals greater opportunities to display their species-specific behaviour while avoiding the routine use of painful procedures, group housing of unmutilated animals sits at the core of the new animal welfare paradigm driven by consumer demand. Group housing is associated with increased risks of damaging behaviours among the animals, such as feather pecking, aggression and cannibalism in laying hens and tail biting, bellynosing, excessive aggression and cannibalism in pigs. Recent research suggests the key to reducing the incidence of these behaviours lies in refining and applying methods of genetic selection, and developing husbandry innovations that improve early and later life conditions - which is exactly what GroupHouseNet will use the COST Action framework and tools to do. GroupHouseNet brings together researchers and industrial partners dealing with animal breeding and genetics, animal nutrition, epidemiology, engineering, animal behaviour and welfare, epigenetics, immunology, (neuro)physiology, economics and ethics. To strengthen the scientific and technological basis in these areas the Action will facilitate knowledge sharing, creation and application in pigs and laying hens in both experimental and commercial environments. The activities will be conducted in an open, output-oriented transnational, multisectorial, and multidisciplinary research and development network emphasising COST Excellence and Inclusiveness Policy.