Only last month the Department of Culture, Media and Sport, published a list of prestigious sites to be recommended for world heritage status. If these submissions are accepted by UNESCO, then some of this country's finest historic mills, factories, docks and public buildings will share the status of the Pyramids.

Only last month the Department of Culture, Media and Sport, published a list of prestigious sites to be recommended for world heritage status. If these submissions are accepted by UNESCO, then some of this country's finest historic mills, factories, docks and public buildings will share the status of the Pyramids. Some may find such comparisons slightly far fetched, yet these buildings are an important piece of our heritage, and represent the pinnacle of architectural and functional achievement during Britain's time as the workshop of the world. Each of them are symbols from a time of momentous change and innovation, physical expressions of profound human endeavour, which, in their context do deserve - I believe - to stand alongside other wonders of the heritage world.

Former industrial and service buildings like these are as much a part of our national heritage as the more commonly revered cathedrals, palaces and country houses. They were often built to the very highest architectural standards of their day and built to last, so that despite the passage of time, many remain in remarkably good condition. For the communities which grew up around them they stand as important landmarks, and many continue to carry the collective memory of those who worked in them. They are links to our past, although their original purpose has now gone. The world has moved on, and we have inherited an astonishing legacy of abandoned industrial buildings, many of great architectural or historical importance, for which there in now no obvious use. As you can imagine, there is considerable pressure to demolish many of them, as it is claimed they stand in the way of new development. Indeed, an enormous number of such buildings have already been razed to the ground in the last thirty years in a rush of collective blood to the head.

For all these years, when visiting communities throughout this country, I have watched in despair as one great building after another has been swept away, with no realisation of their potential for conversion to new uses. Now, at last, there is a growing demand that they be brought back into use for new purposes. People like the character of such buildings, with their symbolic significance, their well crafted details, their landmark status, and the sheer elegance which many still retain. It is all a far cry from the cheap 'tin shed' warehouses, ugly utilitarian offices and nondescript workshops which characterise so much of this country's efforts in urban regeneration and economic development. Yet there are signs that the affection which many hold for these buildings is now finally finding more favour with developers who are begining to discover their potential.

The recent publication of figures on the amount of land needed for new house construction has concentrated minds wonderfully. People are at last seriously looking at the implications of an inexorable march of construction on to green fields and are thinking more creatively about the alternatives, whether building on reclaimed land in our towns and cities, or refurbishing and re-using buildings which have lost their original purpose. Many are already finding that there may be something better than opting for what may turn out to be a soulless housing estate - and many, too, are beginning to appreciate the advantages in being closer to work, to shops and to leisure facilities, if the quality of the environment is good. I doubt that people instinctively want to spend their working lives on anonymous industrial estates and monotonously similar business parks, where even a lunch time sandwich involves a car drive.

We are at a point in history when we have the opportunity to enable new communities to flourish by harnessing the inherent value of the existing build environment and bringing new and exciting life to it. The challenge is to catch the popular imagination with a policy which will conserve our precious countryside, use the many resources in our cities which now stand idle, and so help to create a more invigorating and diverse community life. In the past cities were shaped by the needs of large scale industry, but the development of a more knowledge-based economy and a world of smaller, high-value businesses, often linked to new technology, presents people with a wider range of choices. More jobs and enterprises are likely to be created at a very small scale, clustered together in supportive networks, both virtual and physical. In this new and more complex set of conditions, the quality of the urban environment can be a fundamental influence on the levels of economic success. The communities which flourish will probably be those where people choose to live and work. Yet it is evident in many cities that historic industrial buildings, many abandoned for years, can provide exactly the kind of environment which people need and want for work, for home and for leisure. People want modern amenities and contemporary interiors, but all the more so when contained within elegant, splendid, even stunning historic buildings. Manchester is a good example. Some of its extraordinary legacy of Victorian and Edwardian warehouses, mills and workshops, much of which has lain unused for years, even decades (if it wasn't completely demolished), now provides homes, cafes, restaurants and workspace for a flourishing city centre community, whose population has risen from 400 to 6000 in just seven or eight years. But there are many more memorable buildings crying out for conversion.

I am not talking about the restoration of heritage industrial buildings solely because of their architecture, nor the creation of a 'theme park Britain' where we repackage our heritage merely for the benefit of tourists. But there is no doubt that these buildings, and the environment in which they stand. can provide a uniquely attractive atmosphere for modern living. Above all, we need to rediscover the ingredients for such an atmosphere and try to emulate them in future. Heritage industrial buildings need to be used and adapted for new purposes and I am deeply impressed with the many examples I have seen where such success has been achieved. Dean Clough in Halifax and Salts Mill in Saltaire are two better known examples of large scale mill conversions, but just as significant are areas where many smaller buildings provide opportunities for very substantial urban regeneration. The Castlefield Canal Basin in Manchester, the Calls in Leeds and Nottingham's Lace Market have all been revived by such an approach.

In case I am instantly accused of arguing that we should seek to re-create these heritage buildings as we think they originally were, I am not actually suggesting that we try to build a better yesterday. We should encourage and welcome appropriate new additions and adaptations to our heritage industrial buildings which can help bring new vitality. Sensitive contemporary design can add to the value of an old mill or warehouse and open up opportunities for the future.

I have visited factories, warehouses and mills now being used as offices, art galleries, workshops, housing, restaurants, high value precision manufacturing and many other uses. I am not entirely alone in concluding that you can do just about anything required of a modern economy in a refurbished heritage industrial building. (Try converting a modern building to new uses and see what happens!) Indeed they are ideal for creating flexible workspace where people can start businesses at low costs, where they can be allowed to innovate, succeed, or even to fail. The former Spirella Corset factory in Letchworth is an outstanding example; Bennie Gray's Custard Factory in Birmingham is another. Providing cheap workspace for over a hundred small design businesses - including some started by my Prince's Trust - it offers a highly successful environment for those who otherwise would struggle to establish themselves in isolated and often inappropriate premises. It has restored Alfred Bird's original 19th century custard factory whilst also creating genuine employment for local people, living proof that a multiplicity of uses in one building can create a dynamic where businesses thrive from proximity to each other.

Yet, despite all this, public and private policy makers seem obsessed with putting up new buildings, often at the expense of those that have been standing for many years. Of course some buildings are unsuitable or unworthy of retention, but too often the presumption is for demolition. We could take better advantage of the buildings we already have if funding arrangements were simplified, and a longer term view taken so as to give developers and regeneration agencies sufficient time to do a decent job. I say this after some considerable experience gained through two relevant initiatives I have helped to set up - Regeneration Through Heritage, an advisory team to help project promoters, and The Phoenix Trust, a dedicated Building Preservation Trust, which is directly undertaking the redevelopment of the first of its many major projects at Stanley Mills in Perthshire.

Tomorrow I will be visiting the Great Western Railway Works in Swindon to address a conference on the potential which industrial buildings offer for contemporary uses. The Great Western Works stood empty for many years until a partnership involving the local authority, English Heritage and the Anglo-American company, BAA McArthur Glen, came together to offer a new vision for these amazing, but abandoned buildings. BAA McArthur Glen applied the successful retail formula which it has developed in the fashionable shopping malls of the 'New World' to one of the most important heritage industrial buildings in the Old.

Swindon now has a shopping centre in the middle of town which people can reach by bus, train or car, and the country has saved 40 acres of green fields. I hope that before people rush to demolition in future they will look to buildings like this as classic examples of what can be achieved and make a presumption in favour of re-using many more of our existing historic buildings. I hope too, that the new Regional Development Agencies and the Heritage Lottery Fund, which have done so much to help conserve our industrial heritage, will see that in the long term, investment in these buildings will help to retain our distinctive built environment, whilst offering real solutions to today's urban problems. Apart from anything else, I feel we owe it to those craftsmen who built these buildings with such skill and pride.