Norbert is 44, overweight and balding and, in his snugly fitting denim shirt, cut off at the armpits and unbuttoned to below the chest, he is waiting impatiently for Fraeulein Right to come along. "She should have long, dark hair and I like a woman to show her legs - so short skirts, please. And she should have a personality just like mine," he says.

Although Ilona's ideal partner would be tall and powerfully built, aged between 30 and 40 with a fondness for children and animals, she would happily settle for less. In fact, Ilona is so determined to find a mate that almost anyone will do. "Hair colour, looks and star sign don't really matter. The main thing is that I have someone to lean on," she says.

Norbert and Ilona are among thousands of Berliners to appear on Spreekanal, one of four television stations in the city that fill hours of airtime each day with lonely hearts videos. They are also part of the German capital's fastest-growing social group - an estimated 830,000 people who live alone.

Nobody knows how many singles live in Berlin, but official statistics show that only half of the city's 1.2 million people aged between 25 and 45 - the preferred age for marrying - have tied the knot. And the trend is becoming more pronounced as a growing number of families move out of the city to the countryside nearby. Berlin is expected to lose 400,000 of its three million inhabitants within the next 10 years - almost all of them families fleeing the hectic pace of metropolitan life.

Berlin has long been a magnet for the eccentric, the angry and the unusual but, since the Wall was destroyed 10 years ago, the city has attracted a new breed of entrepreneurs and adventurers hoping to make their fortunes in the new capital. Most of these newcomers are single - at least when they arrive in the city - and they have spawned a huge industry based on combating loneliness.

Three dozen dating agencies offer the most direct route to a potential partner, but Berlin's 90 dance schools and numerous evening classes could not survive without their quota of loners on the look-out for love.

The city's leading tabloid newspaper runs a regular series of profiles of "Berlin's most eligible bachelors", with photographs of melancholy-looking businessmen relaxing in vast, empty apartments. Most of these eligible gents claim that they are yearning to meet the right woman, to settle down and start a family. But many of Berlin's new breed of singles are quite happy the way they are - and they have no intention of letting love interfere with their successful, high-powered lives.

"I hate the everyday and the idea of looking at the same partner every evening bores me to tears. I believe more in quality than quantity; it's better to see each other just twice a week, but intensely," says Martina Bohne, a 30-year-old arts administrator who moved to Berlin nine years ago.

Some complain that the sheer number of single people makes sustaining a relationship more difficult - because there is always another possible partner on the horizon. "Especially here in Berlin, where a disproportionate number of people live alone, people decide more easily against continuing a relationship," according to advertising executive Thomas Heilmann.

As they explore new ways of organising their lives, Berlin's singles are beginning to mimic the lifestyle of the city's large gay population. Discriminatory laws banning gay marriage have, among other factors, forced homosexuals to create alternatives to the traditional family structure, with networks of friends playing a more important, emotionally supportive role.

Bohne believes that good friends can often be more valuable than a partner, not least because they are less emotionally demanding. "You can tell a friend: sorry, I'm not in the mood this evening, I've something else on. Friends forgive that more readily than a partner in a relationship, with whom things are emotionally deeper, more demanding and more complicated," she says.

Many of Berlin's singles are aching for something deep, demanding and complicated, however, and 1,000 of them cram into a tent off the Unter den Linden each fortnight to try their luck at Fisch sucht Fahrrad (Fish seeks bicycle), the city's most popular singles party. Organised by Berlin's leading listings magazine, which also carries thousands of lonely hearts ads, Fisch sucht Fahrrad has something of the atmosphere of a teenage disco.

Each guest wears a number, and interested parties can leave messages for one another on a giant notice board. These numbers can also identify advertisers in the magazine's lonely hearts pages, offering prospective partners an opportunity to make an anonymous assessment of each one's physical charms.

But Berlin's countless bars, cafes and restaurants remain the city's prime arenas for flirting, and the singles boom has helped many to survive Germany's recent period of economic gloom. But love can be found anywhere, even at the launderette on a rainy Sunday morning, as visitors to Berlin's five "launderette cafes" can testify.

During the hour or two it takes to wash, rinse, spin and dry the wardrobe of a one-person household, singles can enjoy a leisurely breakfast, read the papers and perhaps exchange a few words with their neighbours.

Others find love at events such as "Dinner for One" or "Eat and See", where one person cooks for a group of strangers, chosen on the basis of their age and interests, each of whom contributes to the cost of the meal.

There are opportunities, too, at Berlin's annual techno festival, affectionately named the "love parade". An estimated 1.4 million people attended this year's event last month to revel in the world's biggest celebration of mutual extraction of every kind.

Dance teacher Helge Vorthaler claims that, if lonely hearts want to meet the right person, they should look no further than their local Standard, Samba or Tango class. "As far as I'm concerned, singles are people without a dance partner," he says.

For women like Bohne, however, few men can compete with the excitement she derives from her work and, when she looks at her professional life, partnership appears dull in comparison.

"Let's be honest. Work is always stimulating, exciting and new and it should remain like that. But partnerships diminish in power and momentum as time goes by. Where does the creativity and the elan go? That's why work, especially in its euphoric phase, always takes first place," she says.