By Andrew Harding
BBC News, Shenzhen
Millions of people are leaving rural China and heading to the cities in search of work and prosperity. New towns are springing up and growing quickly, turning quiet seaside villages like Shenzhen into vibrant industrial centres.
Shenzhen: from a village to a city in 30 years
Liu Xiao Yi comes from a small village in the mountains of south-western China.
He is 36 now, with flecks of grey hair above his ears, a quick grin, and wiry body.
When he was 10, his mother died, swept down a hillside during a flash flood.
"You would not believe how steep those hills were," he says. "Some of the rice fields were no bigger than this table."
We are sitting in the room that he, his wife and two children share with another migrant family in the vast drab suburbs of a city that seems to grow as you watch it.
Thirty years ago Shenzhen was a fishing village. Now it is an ocean of factories and tower blocks.
At the age of 11, Liu was made aware that he was now a burden on the family, and needed to leave
The population is 11 million and rising.
Liu's father was a farmer.
"We were very poor," he says.
At the age of 11, Liu was made aware that he was now a burden on the family, and needed to leave.
"That's how it started," he says. "I walked to another province and got a job mending shoes.
"I stayed with a man who knew my family. That lasted a year.
"After that I worked in an illegal tin mine.
"There was this tiny entrance you had to squeeze through, and then carry out these huge bags of rock.
"Everyone else was much bigger and stronger than me."
He bends over double to act out the scene.
Like most migrants they started off in factory jobs, staying in single sex dormitories
"When I was 15, I heard there was construction work going on the island of Hainan.
"I spent a long time there, doing a bit of everything. Mixing concrete, learning about electrical wiring."
Towards the end of his time on the island, Liu went home to get married to a woman from a nearby village.
"We just signed the forms and that was that."
Her family were not too pleased with the match.
"They were hoping for someone richer." He laughs, and so does she.
Today Liu and Wang Yu are still a team, and visibly infatuated.
You could paint Liu and his family as victims of China's frenzied economic transformation
They moved to this city 10 years ago.
Like most migrants they started off in factory jobs, staying in single sex dormitories.
Wang remembers 12 hour days earning 6p ($0.11) an hour in some electronics factory.
"But we wanted to be together," says Liu, "so we started selling things instead.
"We've sold everything, from fruit to key rings."
Now he has returned to his very first job - mending and selling shoes - factory rejects.
There are shelves of them on the damp wall at home, next to an old poster of Chairman Mao, and a slightly crumpled picture of Britney Spears.
Their two sons, aged 10 and 12, are wrestling on the floor in a giggling heap.
You could paint Liu and his family as victims of China's frenzied economic transformation.
Their home is cramped and crawling with rats. Between them, they earn maybe £100 ($187) a month.
Liu is in debt.
After 25 years of work, Liu says he has precisely 16 yuan - about 1p ($0.02) - in his bank account
He cannot afford a permit so he and Wang work illegally on the street, selling their shoes on a crowded overpass.
They have to watch out for the police and criminal gangs, all looking for protection money.
One local gang stole Liu's bicycle recently. He had to pay a huge fee to get it back.
After 25 years of work, Liu says he has precisely 16 yuan - about 1p ($0.02) - in his bank account.
But that is not the whole story.
Wang puts down her knitting and leans back on their bed.
"I miss the clean air in the village," she says.
The family dream is to save enough money to build a house back in the mountains
"But we're much wealthier here than we would be back home."
They have an old TV, and a DVD player.
A few months ago they finally decided they could afford to bring their children to the city to live with them, instead of leaving them with Wang's parents.
The schooling is expensive here - about £200 ($374) a term for both boys - but it is far better than in the countryside.
Liu takes a call from a friend on his mobile phone.
The family dream is to save enough money to build a house back in the mountains.
"Somewhere for my father," says Liu.
It is a dream which sustains them, and millions of other Chinese migrants as they struggle to cash in on an economy booming by around 10% a year.
I heard no talk of democracy or revolution.
People either rail against official corruption, convinced a creaking system can be reformed, or simply turn their backs on the state altogether and focus on squeezing as much over-time as they can out of their factories.
It is dark outside, and Liu offers to take me on a ride around the neighbourhood on his beloved bicycle.
I perch on the back and we race along narrow alleys and out into a big street crowded with migrant workers in their identical factory uniforms.
We stop to buy some oranges from a stall and watch the crowds swirl around us.
A blur of energy and poverty and optimism.
From Our Own Correspondent was broadcast on Saturday, 7 October, 2006 at 1130 BST on BBC Radio 4. Please check the programme schedules for World Service transmission times.