"Listing began in Britain on January 1st 1950, under the austere post-war Labour government; a surprise to many who believed that conservation and conservatism went hand-in-hand. Sadly we were not pioneers in the field; the French had been classifying historic buildings for the previous hundred years, while we in Britain had to rely on pressure groups such as the Georgian Group, formed in the 1930s to prevent the wholesale destruction of our Georgian architecture, perceived at that time as dull and lacking in merit. How opinions change. Over to English Heritage:

Historic buildings are a precious and finite asset, and powerful reminders to us of the work and way of life of earlier generations. The richness of this country’s architectural heritage plays an influential part in our sense of national and regional identity. Your favourite views of England - street, village, town or city - almost certainly contain buildings protected by the process called ‘listing’.

English Heritage has the task of identifying and protecting this inheritance in England. Our main means of doing this is by listing - recommending buildings for inclusion on statutory lists of buildings of 'special architectural or historic interest' compiled by the Secretary of State for Culture, Media and Sport.

Why is a building listed?

Listing is not meant to fossilise a building. Its long-term interests are often best served by putting it to good use. If this cannot be the one it was designed for, a new use may have to be found. Listing ensures that the architectural and historic interest of the building is carefully considered before any alterations, either outside or inside, are agreed.

How are buildings chosen?

Buildings can be listed because of age, rarity, architectural merit, and method of construction. Occasionally English Heritage selects a building because the building has played a part in the life of a famous person, or as the scene for an important event. An interesting group of buildings - such as a model village or a square - may also be listed.

The older a building is, the more likely it is to be listed. All buildings built before 1700 which survive in anything like their original condition are listed, as are most built between 1700 and 1840. After that date, the criteria become tighter with time, so that post-1945 buildings have to be exceptionally important to be listed.

The grades (different in Scotland and Northern Ireland)

The buildings are graded to show their relative architectural or historic interest:

• Grade I buildings are of exceptional interest

• Grade II* are particularly important buildings of more than special interest

• Grade II are of special interest, warranting every effort to preserve them

Listing currently protects 500,000 or so buildings, of which the majority - over 90% - are Grade II. Grade I and II* buildings may be eligible for English Heritage grants for urgent major repairs. You are extremely unlikely to get any sort of grant for a Grade II or C listed building."



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Note added at 7 mins (2005-10-20 07:57:40 GMT)
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In other words, if a building is listed, it is protected by law from alterations which would not preserve the character or historical interest of the building. It's part of the attempt to conserve buildingsw that are an important part of Britain's heritage.