Important components of farm animal welfare are the assessment and alleviation of pain and stress during and following routine husbandry procedures used on farms (e.g., disbudding and castration of calves). There is now a higher level of public awareness and concern for animal welfare on-farm, and in recent years consumer demand has placed pressure on agricultural industries to provide ‘welfare friendly’ products that also meet high standards of food quality and safety. The assessment and management of stress in farm animals have been reviewed previously. A major issue for animal welfare research is that currently most of the techniques and methods we use to measure stress or pain are invasive (e.g., blood sampling) and there is a lack of non-invasive, reliable tools. This article provides a concise review of new technologies and tools to evaluate the welfare impact of different husbandry practices in order to improve animal welfare.