Delhi, the largest of all cities attending LivCom with a population of 16.3 million, is gearing up for its biggest ever sporting event, the Commonwealth Games in 2012. The city is also bidding to run the 2014 Asian Games. "It has kept us on our toes," said Jitendre Dadoo, secretary of the environment department. "We needed to improve a lot of systems anyway, but it now means we have to do it."

Mr Dadoo predicted that traffic jams would be a thing of the past now that Delhi has built 50 flyovers with another 50 scheduled before 2012. A new metro system covers 25% of the city and a new airport is being built, while the honking of horns is now forbidden between 10pm and 6am.

Another aim for 2012 is to create 33% forestation and tree cover in the city; 25 new forests are planned, with the help of schools and colleges volunteers. Under the Preservation of Trees Act, citizens have to plant 10 trees for every one they cut down.

Renewed enthusiasm for the ancient practice of yoga is revitalising health in India. Mr Dadoo said: "There has been a discernable reduction in diseases like cancer, diabetes, asthma and blood pressure-related illnesses; people are not having to go health clinics so often.

"If you do yoga for 30 minutes a day, none of these diseases will enter your body. I used to be a diabetic but now my situation has greatly improved."

One of Dongguan’s main aims is to involve its people at every step of its development. When half a million people were invited to vote and comment on what they thought were the eight most scenic spots in Donguan (population 4 million), 435,000 returned their questionnaires.

Donguan has been voted a National Green Model City, a National Sanitation City, the national basketball city – it has been CBA (Chinese Basketball Association) champion three times – and in 2004 was voted by China TV to be the Most Charming City.

It has 410 Green Communities and is aiming for another 150. "This is a totally democratic process because the representatives of each community make their own charter for the environment, on a voluntary basis," explained delegate Carol Chu, a Donguan citizen who runs international golf competitions.

"We give the programme regular publicity and find that people want to be involved because the citizens find that property values increase and that places are more beautiful to live in if they look after them. "The community members realise that things like energy saving and recycling saves them money, and that gives them further encouragement."

The creation of Abuja (population 3.1 million), the new capital city of Nigeria, is described as a "challenge of courage". "It is not easy to establish a city from scratch," commented Luka Bulus Achi, the director of parks and recreation in the city.

"We found that Lagos, the old capital, was not fulfilling our requirements and so we started building Abuja in 1976. There were 33 settlements already there, so one challenge was to protect the people who were already there and remember the city’s origins."

One original settlement, Ushafa, a "corridor of cultural diversity" is famed for its pottery and has been visited by the former US president Bill Clinton.

Abuja has had "100%" success in getting rid of the carbon monoxide pollution caused by motorbikes. "A month ago we banned their use and people are only allowed electrical ones. Gradually people have realised that life is much better and we have had several phone calls and letters to say what a great improvement it is."

The city has also had success with replacing lighting at bus stops, offices and in the streets with solar power and by encouraging biologically soluble soaps for domestic use.

Abuja is also making progress in combating HIV and AIDS. "The distribution of ARV drugs is subsidised and we make a great effort to make HIV and AIDS sufferers feel that they can come out of their homes and be recognised," explained Mr Achi. "It’s a psychological campaign as much as anything else; our mayor is very active in this and he organises dinners for patients so that they do not feel ashamed. We try to make them feel as much part of the system as everyone else and give them jobs."

Lebohang Raliapeng, director of the environment management department of Ekurhuleni, South Africa,described his home city (population 2.5 million) as "coming from humble beginnings to having world-class freeways connecting with the whole of South Africa"

The city’s claim to fame is as the site of the discovery of the world’s largest diamond – 3106 carat – in 1905, 21 years after gold was first discovered in the region.

"When the city embarked on its programme of change, most of its infrastructure was old and subject to breakdown. Our 2025 agenda includes the aims of productivity, inclusivity, sustainability and good governance," said Mr Raliapeng.

He said the chief aim is to halve poverty and unemployment, currently running at 30 and 40% respectively, by 2005.