The wealthy living shoulder to shoulder with the poor is a feature of most large cities across the world, but there can be few places where the contrast is as extreme as Mumbai.

Rumoured to have more millionaires per square mile than Manhattan, property prices in the city are up there with New York, Hong Kong and Tokyo. Yet half of the population is living in slums, some in authorised permanent structures with electricity, some in unauthorised structures liable to be torn down at any time, and others living on the pavements.

You first become aware of this even before you land. As the plane descends towards the airport, rows of corrugated iron huts seem to stretch for miles with the bright lights of downtown twinkling in the distance. Chhatrapati Shivaji International Airport is hot and chaotic, perfect preparation for the city itself.

Our first attempt to catch a taxi doesn't go too well. On the way to the taxi rank, our luggage is wrestled from us and taken to an official looking taxi a few metres away from the rank. No sooner have we gone round the corner and we are turfed out of the car and shown to another, not-so-official looking car while our first driver heads back to arrivals to pick up his next unsuspecting passengers. Not wanting to risk a trip in an unlicensed car that looks likely to break down at any minute, we wrestle our luggage back from the new driver, walk the 200 metres back to the taxi rank and eventually sink gratefully into the leather seats of one of the ubiquitous Ambassador taxis with an extremely chatty driver.

The journey from the airport to our hotel on Juhu beach takes us past more slums, with mothers carrying small babies tapping on the car windows to ask for a few rupees every time we are stuck in traffic, which happens regularly in Mumbai. Advertising hoardings for mobile phones and the latest Bollywood releases compete with the slums for space along the roadside, and every so often the rows of shacks are broken up by small temples lit up with fairy lights.

It's difficult to describe Mumbai without overusing the word ‘contrast', but that's exactly what we feel as we entered the air-conditioned marble lobby of the Marriott Hotel on Juhu beach. Down the wide steps from the lobby was one of several restaurants and then huge windows looking out to the pool area and, beyond that, the beach and the Arabian Sea. We had landed late at night so are too tired to check out the Enigma "bar and nightclub", but judging from the glamorous outfits of the mumbaikars making their way down the stairs, it is definitely one of the places to be seen in Mumbai.

After breakfast, we have time to explore the beautiful pool complex with its resident crows and to check out a few of the expensive shops in the hotel before I head off to my arranged meeting with the director of an organisation working with some of the city's street-dwellers. Although only 30 minutes away (and most of that in non-moving traffic), it is a world away from the wealth and glamour of the JW Marriott.

The Bandra East Community Centre is a voluntary organisation that provides shelter, health care and training for both the young and old living in the slums or on the pavements of Mumbai. As I arrive, a group of children are playing cricket in the dusty courtyard and Father Cyril D'Souza, the director of the centre, comes out to greet me. He shows me the crèche which allows parents (and older siblings) to go to work knowing that their children are being cared for.

Upstairs, sewing, typing and computer classes are taking place. Father D'Souza is keen to buy more computers as the classes have enabled many of his students to find work, and I realise that it's not just the wealthier Indians who are looking to take advantage of the country's booming IT industry. Finally, he shows me drop-in centre where street children can come for food, a wash and clean clothes; and the nursing room for children who have been injured or fallen ill. Sadly, they regularly have to turn children away due to a lack of beds. 

I return to the hotel feeling upbeat (via a couple of tourist-trap shops - "I get a free t-shirt if I bring them enough customers", the driver explained), impressed with the dedication and optimism of Father D'Souza. That evening, I take a walk along Juhu beach as the sun is setting and everyone in Mumbai - young and old, rich and poor - seems to have had the same idea. The smells from the food stalls and the music from their radios replace the pollution and car horns, and I enjoy the contrast of the Indian and UK climates.