Imagine you are a woman, a Guardian reader, and you work in finance. Do these people exist? Yes, they do. Would they talk about their experiences? A dozen just did. So what is it like for them, and what do they think are the chances of more women making it into finance?

Research suggests women are more likely to avoid the excessive risks that helped to produce the current financial mess. Or, as IMF director Christine Lagarde quipped: "If Lehman Brothers had been Lehman Sisters, today's economic crisis clearly would look quite different."

Yet on the ground it seems more complicated than that. Speaking to women working in finance, the gulf between the City insider and outsider seems greater at times than that between the sexes. You get more flak from outsiders for working in finance, they say, than for being a woman in the industry itself. So the IT business analyst at a major bank in Canary Wharf says: "When I told my family I had taken this job, a silence fell over the table. Then my sister said: 'You're one of the bankers now.'"

Another woman, who is in her early 30s and works as a fundraiser at a sharia-compliant venture capital firm, says: "Some people [outside finance] need to see that you have made a pact with the devil, compromised something. They want me to be one of those lonely career women with nothing in her fridge but one bottle of champagne and a carton of milk, out of date. And then there is the moral grandstanding. You may have this great job that pays really well and which, apparently, you even enjoy. But. You. Are. Evil. And I may be an underpaid teacher. But. I. Am. Good."

I had always thought of finance as a bastion of sexism; why else do you find so few senior women there? These interviews suggest that the truth may be more subtle, but let me first explain how they came about.

Seven weeks ago I started an experimental blog on theguardian.com. The idea is to make the world of finance accessible to outsiders by portraying people from across the sector. The first batch of 10 interviews were all men, for the sad and simple reason that I had not found any women. Then the blog went online and within a few hours female volunteers began to appear in the jlbankingblog@gmail.com inbox. This seemed a golden opportunity; how often do you hear a woman talk in her own words about the world of finance?

Their voices help show just how vast and diverse the financial sector is. I had not even heard of a "bond pricer" before I met one for this series. All 12 women gave the same reason for participating: to contribute to a better understanding of the financial sector. All agreed that changes were needed, a few said "big changes". They also said that most people in finance don't work in the areas that caused the crisis. Most are not with institutions bailed out by taxpayers' money. Most don't make the huge amounts you find in newspaper headlines.

Our meetings often felt like clandestine journalistic blind dates. I'd sit in some coffee bar in Canary Wharf, Mayfair or around St Paul's and with every woman who came in, I'd think: is that her? We would talk and I would write up their words into a monologue, run it past them on their private email for verification and post it online. Well, most of the time. One volunteer backed out prematurely, saying: "If anyone ever found out I could be fired. And I'm fairly low in the hierarchy so can't really afford to take that chance right now."

One saw the transcript and begged to be excluded. Anything that might identify her had been purged, but no matter. I could quote only disembodied parts about her work in risk and compliance (investigating fraud and errors). Such as this: "There is a glass ceiling in finance but not in a formal sense. If you want to get to a real senior position, you have to become buddies with the senior managers, who are still all male. These men constantly hold meetings together, travel together, eat together … They need you to fit in. You need to play golf, blend in with the casual banter … When a woman joins such a team, its dynamics change. This is a very important barrier."

The fact that 12 women risked their jobs to speak to a Guardian journalist contradicts the notion that women are more risk-averse. They took the risk but seemed more aware of it – and more willing and able to acknowledge the accompanying emotions. Before an interview went online I would drop them a line. Many would respond to say how nervous they were. This never happened with the men. Either they aren't nervous (as men they are less identifiable) or they won't own up to it.

There was little bitterness or whining in these interviews, all of which can be read in full on the Guardian website. Here is the head of a marketing department for a European bank: "Anyone can do this job. What you need is self-belief. I don't have a degree in anything financial, or marketing for that matter. There's a fair amount of deadwood in this industry, what you need is determination to outshine others. How I ended up in finance? I needed to bring up my child on my own. That means I had to find a job that paid double, essentially."

Her advice to other women: "Don't make men look too stupid."

None of the women reported blunt sexism of the Mad Men kind. The stockbroker was old enough to remember those days, only 20 years ago: "On the trading floor, men would chew paper into little papier-mache balls and try to shoot them up my skirt. They'd actually reach into the aisle to throw them. If this happened now, you could sue. Those times were different."

Some even regretted the changes. The childless IT analyst says: "Banks these days are incredibly PC about motherhood. They are really trying too hard. There's always some scheme or stand promoting the next workshops for mothers-to-be. One week it's diversity week, the next it is I don't know what week…"

What's holding women back? An investment management adviser, who is in her late 20s, says: "At university, it was 50:50 male/female. You felt there was simply no difference. Then we enter the workplace and I have seen peers I knew from university change their behaviour. They were influenced by older men, and their sexism."

There is the male-bonding during strip-clubbing, football and cricket corporate events. There's the golfing, and Middle Eastern clients who refuse to deal with women. But a real killer is maternity.

The fundraiser says: "This job is not like teaching, where you can step out and back in with relative ease. When you come back, you need to be retrained because so many things have changed. If you then announce after six months you're pregnant again … How do you expect a manager to react? A colleague was offered $1m to leave, after announcing her second pregnancy. It wasn't about the money, the firm was losing so much more through the disruption."

None was in favour of quotas. "I would hate to make a promotion on my gender rather than competence," was the refrain. The chief operating officer running a 400-strong trading floor in Canary Wharf explains that any suggestion that she was not there on merit would undermine the authority on which her job depended.

The officer in risk and compliance talked about "push back" – when people flatly refuse to hand over documents: "I ask somebody for something, and they refuse it point blank. So you send them an email stating your request, and then you 'escalate'. Ask your manager to ask him. Ask your manager to ask his manager."

In games of chicken like this, women say, you can't be seen to be in your position because of quota as they'll simply push you over. Who would have thought that some of the fiercest opponents of quota for women in finance might be those already working there? The premise of quotas is that more women would want to work in finance. But, says the stockbroker: "I have sat on female recruitment committees but I warn them, this is not an easy place to work. The simple fact is that fewer women want this lifestyle than men. Women, quite rightly, often have other priorities. If a man is more committed to the job, puts in more hours and effort, then he is going to be more successful. If you want to last in this industry, you need to behave like a man."

Is that the conundrum, then? You want more women in finance because on average they are more rational. But many women opt out of such a career for exactly that same reason: they are too rational to sacrifice their life to work. It would be great to get more women, and men, to write in on this.

The crisis was caused by greed, says the consultant. But what is driving it? "I'd say the competitive macho culture, testosterone … I have to be better than the next guy, so I have to make more money than him because that is proof that I am better." How to change this? "They try it with ever more regulation. That's attacking the symptom. I genuinely have no idea."