Mr Pratchett's decision to discuss his diagnosis of Alzheimer's disease is a brave one. It is all the more encouraging because of his resolve to remain so positive in the face of what he calls an 'embuggerance'.

Alzheimer's disease is the most common form of dementia, a progressive condition affecting 700,000 people in the UK and millions more carers. This includes 15,000 younger people with dementia who like Mr Pratchett are diagnosed before they are 65.

Mr Pratchett's commitment to continue working reflects the experiences of many people, who in the earliest stages of dementia will work and socialise with the support of loved ones and carers.

The Alzheimer's Society is available to support Mr Pratchett and families affected by dementia across the country, by providing information and support and with a research programme into the care, cause and cure for the condition.