<p>Pain is recognised as: ‘an unpleasant sensation that warns of potential or actual tissue damage’ (Drago 2005). How a person perceives pain is subjective and widely acknowledged as being ‘what the experiencing person says it is, existing whenever he says it does’ (McCaffery 1972). It is accepted that the ‘gold standard’ of pain measurement is self reporting (SIGN 2000, Davies and Evans 2001, Zwakhalen et al 2004) and in the general population this may be a straightforward process. However, people with learning disabilities may be unable to express pain verbally, thus increasing the risk of progressive damage (Rutledge and Donaldson 1998) if carers do not respond appropriately to changes in behaviours, demeanour or vocalisations.</p>