The Landmark programme is very keen to tell you what it's not. It's not promising anything, it's not self-improvement, it's not going to analyse your entire life through some sub-Freudian Oedipal lens. And yet, it does promise the world. On the evening I went, I lost count of the number of people who told us how, after the Landmark experience, they'd suddenly discovered who they really, really were. For a surprising number, this realisation took the form of a sudden need to tell their mothers (hard–working, selfless souls to a woman) how much they loved them. But how do they manage it?

Landmark is big business. According to Time magazine, 725,000 people have signed up for the three and a half day 'Landmark Forum'. GQ magazine placed it as one of the top ten adventure weekends in the world, just behind space travel. So far, so promising.

So, ready to change my life, off I set to Landmark's rather impressive offices in Mornington Crescent, for the 'Special Introduction to the Landmark Forum'.

On arrival, everyone registers and is given a name tag (white for newbies, green for 'graduates' who have already completed the course). Apparently, most of the 200 or so people here have been brought along by a friend keen to spread the Landmark message. We are then greeted by Landmark employee Will, a man dressed in what Fergal Keane called, in Letter to Daniel, "the type of self–important little suit young men always wear on their first day at work".

Will used to be a pilot, which is pretty cool. He then gave that up to work for Landmark — arguably less cool. Will tells us how sceptical he was at his first Landmark course, without really explaining why he was there at all. Magically he was converted, called his mother, and told her what an amazing woman she was. Will tells us how much the simple message of Landmark changed his life: the message being…

Well, that's the problem. It's not entirely clear what the message is. The programme seems to combine elements of pop psychology with an odd form of existentialism. At one point, I'm fairly sure, the assembled are collectively accused of 'bad faith', or what Landmark calls 'inauthenticity'. A look through the course syllabus also dredges up concepts such as 'dealing powerfully with breakdowns', where we learn to welcome breakdowns [defined as 'something that we shouldn't be'] "as an occasion for leadership and accomplishment." This deconstruction is intended to lead to some sort of 'breakthrough' after which, presumably, we all become better people. In reality, all that they seem to be promising is a little self–awareness.

The speaker at tonight's event, David Newar, is an impressive performer, striding confidently about the room, informing us that while it may seem like he's addressing the whole audience, he is really talking to each and every person as an individual. This may be standard management seminar patter, but I should confess it actually does make me feel special.

The crowd themselves, each of whom must be feeling as special and tingly as I do by now, look like what Time described as 'well–educated and professional seekers', which is kind of disappointing, in a way. At self–help seminars, you always expect to see people who at least seem worse off than yourself. You know, people who actually need this sort of thing.

This prejudice is something Newar acknowledges, cleverly making us all feel a little bit smart and at the same time taken down a peg or two. Maybe that is Landmark's genius — they very deliberately promote themselves as the self–help course for people who aren't into self–help courses.

Their literature is quick to tell you how studies have shown them not to be religious, or quasi–religious, or cultish. The speakers tell you how sceptical they were of the whole thing when they started off, how they never thought they'd be the type of person who'd benefit from something like this, but…

There's a clever vagueness at play here: it's not really a self–help course, they're not going to promise results, but at the same time, it is self–help and you will get results. No wonder I'm confused. Though clearly not as confused as some of my fellow initiates.

"Anyone here like to get up and tell us what they hope to get out of the course?" asks Newar, whose manner sits somewhere between nice uncle and PE teacher. A hand immediately pops up, jack–in–the–box style, and a young woman who had been sitting front–row centre gets up to announce happily to several hundred strangers that she wants to learn how to say 'no'. Hardly seemed like she needed assertiveness lessons, but hell, why not.

Later, a group of graduates testify how the course has helped them. One woman tells us that, in her 20s, she was quite flirtatious and went out with lots of men. Now, after doing the Landmark programme (and hitting her 30s), she's settled down and has a partner and kids. Amazing. I bet that would never have happened if she'd just gone on a first aid weekend or a training course on tidy desk management.

Someone else confesses a phobia of middle–aged women. Apparently, ever since a female umpire disqualified him from the individual medley at a swimming gala he'd found it difficult to deal with older women. But after finishing the Landmark course he was able to complete a work project with, wait for it, a middle–aged woman! He does qualify this by saying he found the experience a bit tough. But still — breakthrough!

So what have I learned this evening? Erm — not sure. Help with self–help seems a curious phenomenon, especially at £275 per three–day course. But judging by Landmark's proud boasts of numbers and turnover, and, indeed, the number of people who agree to sign up for the initial course at the end of this evening, it's a phenomenon that's not going to stop until the entire world has called its mother to let her know what a truly wonderful person she truly wonderfully is.