Neonates are capable of experiencing pain from birth onwards. An impressive body of neuroanatomical, neurochemical and biobehavioural evidence, which has accumulated over the past 2 decades, supports this capability. This evidence mandates health professionals to attend to the prevention, elimination, or at the very least, control of pain for infants. This mandate is essential since pain is known to have both immediate and long term effects, especially if pain is untreated and is severe, prolonged or frequently experienced. Therefore, pain must be assessed frequently, not only to measure location, intensity and duration but also to determine the effectiveness of interventions implemented to control pain. An impressive array of measures for assessing acute pain in infants exists which incorporates valid pain indicators in this population. However, there is a need to develop new measures to assess chronic pain conditions and pain in infants in acute situations.