To mark the new millennium, this year's Reith Lectures are delivered by five different thinkers, each eminent in a different field. At the end of the run, the Prince of Wales presents his own views on the topic in a roundtable discussion with all five lecturers.

The Millennium Reith Lectures deal with one of the most pressing issues of our time - sustainable development. The first lecture, delivered from London is by Chris Patten.

Chris Patten is a European Commissioner and was the last Governor of Hong Kong. He was also a UK Minister for Overseas Development and Secretary of State for the Environment

In his lecture, Chris Patten discusses the source of authority, the role of law and the need for accountability. He argues that sustainable development is about much more than environment policy defined in terms of departments, ministers and white papers. It requires a mosaic of institutions, policies and values.

Professor Giddens was director of the London School of Economics and he has been described as 'Britain's best-known social scientist since Keynes'.

In his fifth and final lecture, delivered from London, Professor Giddens examines one of the most powerful energising ideas of the 20th Century; democracy. He argues that rather than thinking of democracy as a fragile flower, easily trampled underfoot, we should see it more as a sturdy plant, able to grow even on quite barren ground. The expansion of democracy is bound up with structural changes in world society, but Professor Giddens believes the furthering of democracy at all levels is worth fighting for and can be achieved. Our runaway world, he says doesn't need less, but more government which only democratic institutions can provide.

Professor Giddens was director of the London School of Economics and he has been described as 'Britain's best-known social scientist since Keynes'.

The lectures are delivered from five major cities around the world, locating the lectures themselves within the cultural variety of the world across which they were broadcast.

In his fourth lecture, delivered from Washington DC, Professor Giddens examines the roles within the family and argues that the persistence of aspects of the traditional family, in many parts of the world is more worrisome than its decline. Professor Giddens believes that the most important forces promoting democracy and economic development in poorer countries are the equality and education of women and it is the traditional family that must be changed to make these possible. Sexual equality is not just a core principle of democracy, he argues, it is also relevant to happiness and fulfilment.

Professor Giddens was director of the London School of Economics and he has been described as 'Britain's best-known social scientist since Keynes'.

The lectures are delivered from five major cities around the world, locating the lectures themselves within the cultural variety of the world across which they were broadcast.

In his third lecture, delivered from Delhi, Professor Giddens looks at the links between tradition and fundamentalism and argues that all traditions are invented traditions. Much of what we think of as traditional, and steeped in the mists of time, is actually a product, at most, of the last couple of centuries, and is often much more recent than that. It is a myth to think of traditions as impervious to change. Traditions, he says, evolve over time, but also can be quite suddenly altered or transformed.

The 1999 Reith Lecturer is Professor Anthony Giddens. Professor Giddens was Director of the London School of Economics and his writings have been used by world leaders, including Tony Blair and Bill Clinton, to develop ideas on what become known as 'The Third Way' in politics. He was Professor of Sociology at the University of Cambridge from 1986-96 and took up the post as Director of the London School of Economics in 1997. He has been described as 'Britain's best-known social scientist since Keynes'.

The lectures are delivered from five major cities around the world, locating the lectures themselves within the cultural variety of the world across which they were broadcast.

In his first lecture, delivered from London, Professor Giddens examines the concept of globalisation and how it has affected our lives.

This year's Reith lecturer is British military historian and journalist John Keegan.

In his fifth and final Reith lecture, recorded at the Broadcasting House, London, John Keegan considers the future of war. He argues that it will not be law that will keep the world's peace. Rather it will be because the United Nations retains the will to confront unlawful force with lawful force together with the capacity to resolve the conflicts in which wars originate. He believes that we must not shrink from seeing the causes of war addressed, but equally we must not shrink from seeing violence used when the threat of violence has failed.

This year's Reith lecturer is British military historian and journalist John Keegan.

In his fourth Reith lecture, recorded at the Bute Hall, University of Glasgow, John Keegan considers the impact of battle on those who fight them and how it's altered the nature of war throughout history. He also examines how modern warfare has changed the role and experiences of the soldier.

This year's Reith lecturer is British military historian and journalist John Keegan.

In his third Reith lecture, recorded at King's College London, John Keegan explores the evolving relationship between war and the nation state, the changing nature of sovereignty, and examines whether states need to cause conflict.

This year's Reith lecturer is British military historian and journalist John Keegan

In his second lecture, recorded at the Royal Military Academy Sandhurst, John Keegan looks at the origins of warfare, when combat first became purposeful, and examines whether evidence of violence and the need for war is embedded in human nature, or if it is only present in the external factors which act upon human nature. He argues that the evolution of conflict is inextricably linked to the evolution of social groupings.

The Reith lecturer for the 50th anniversary series, is British military historian and journalist John Keegan. He has been a senior lecturer in Military History at the Royal Military Academy Sandhurst and also held a visiting professorship at Princeton University. Leaving the academy in 1986 John Keegan joined the Daily Telegraph as a Defence Correspondent and remains with the publication as Defence Editor, also writing for the American conservative website, National Review Online. His published work examines warfare throughout history, including human prehistory and the classical era; with the majority of his writing focussing on the 14th century onwards to modern conflict.

In his first Reith Lecture, recorded at the Royal Institution of Great Britain in London, John Keegan explores the great impact warfare has had on modern times. War has been the scourge of this century, but John Keegan argues that until very recently war was not among life's great enemies. War previously had occasionally had epidemic effects, but it always stood lower in peoples' fears than the arrival of famine and disease. The fear of war as a widespread killer, he says, only began in the 19th century, and only in the 20th century did the fear of war overtake the more primordial anxieties associated with sickness and deprivation.