Pain can only be managed if it can be identified and assessed. However, pain assessment in animals is challenging, especially in minimally domesticated species such as some production animals. In production animal species, various approaches are taken to assess pain, including observations of behaviour, measurement of various physiological parameters, infrared thermography, activity levels, gait analysis, nociceptive threshold testing and electroencephalography. Furthermore, scoring systems, which attribute number to the severity or intensity of pain, can be utilised and currently involve the use of uni-dimensional pain scales, composite pain scales and facial grimace scales. Pain assessment for both acute and chronic pain is more comprehensive in companion animal species but given the role of many production animal species in food production, biomedical research, exhibitions and as pets, further research is warranted.