There's the faint discomfort you feel when you peer into someone else's shopping trolley and compare their organic/seasonal/freerange selections with your ice cream tubs and four different types of pizza. Then there's the pang you get when you observe a ridiculously good-looking young family having dinner in a Japanese restaurant, where the parents are straight our of a Ralph Lauren ad and their children ask for more wasabi with their sushi.

But for a blast of lifestyle envy so acute that it almost knocks the breath from your body, a flick through Irish interiors style bible, The White Book, will do it every time. This exquisitely photographed, lovingly assembled glimpse into the alternative universes of the well-heeled and tasteful makes you long for the sort of existence where everything is wenge and marble and beautifully appointed. Not for these people the debris of everyday life, like Chinese takeaway menus, Sunday newspaper supplements and underwear drying on radiators.

Published twice a year, and first making its appearance in January 2004, The White Book Essential Interiors, alongside its sister publication, The Book of Interiors Ireland, have become the coffee-table choices of the design-conscious, not only because of the pleasing aesthetics but also because they're useful.

The White Book, in particular, strives to be as practical as it is aspirational and inspirational, with features on 14 different categories for every room in the house and a directory page to let you know where you can source the designs locally.

"You look at this book and you think, that is the look I am trying to achieve, where can I get it? Or if you want to get it made, you've got all these illustrations and pictures of these gorgeous things, and lifestyle shots as well, in situ, as opposed to just a product shot. You won't see a table sitting on its own, " says 39-year-old Siobhan BuchananJohnston, managing director of Montague Group Publications, the company behind the book, and the book's publishing director.

While she agrees that the products are high end, she argues that the book's function is more about stimulation than it is about consumption. "It's great for people who can afford to go out and spend a lot of money on one of our kitchens or sofas, but do you know, even with myself, I don't necessarily buy everything that's in the book. I might go out and look for a cheaper version but I've gotten the inspiration from the book and that's what we're pushing."

It's difficult not to feel even more lifestyle envy upon visiting Buchanan-Johnston in her offices in Dublin 2. White walls, comfortable leather couches, wooden paneling, black carpet and scented candles make it feel more like someone's very chic home and it's possibly one of the only companies in Dublin which can boost an office dog, the whitest, fluffiest and rather excitable Japanese Spitz, called Montague.

Belfast-born Buchanan-Johnston herself, a former model and journalist, is also suitably glamorous and very obviously enamoured with what she does. She takes a very hands-on role in the book and attends every photo shoot to ensure the end result matches her artistic vision. "I want every page in that book to be a page you can actually pull out and frame . . . it's a piece of art, " she says.

When she hears of an amazing house whose owners aren't too keen on having it photographed, she says she'll "almost stalk them" until they give in. Only homes which haven't appear in other publications make the pages of The White Book. It's expensive to produce, she says, but she won't skimp on the quality, to the chagrin of her financial director, nor will she increase the amount of ad pages in the publication.

"We have 70 pages of advertising in a 320page book. That's a tiny ratio and people think I'm mad. They say 'Siobhan, you've got it all wrong, that's not commercially viable, you're not going to make any money'. But this is a book of passion, it's not just about money, " she says.

She's not reaping huge financial rewards . . . yet . . . but nor is she losing. "A lot of people in business could say I'm doing it for the wrong reasons but I know it's right. I'm building this 'empire', as we call it, absolutely rock solid from the bottom. We just get bigger and bigger every year. We started out with one book that I did on my own . . . that was October 2003 . . . and a girl just helped me at the end with the admin."

That Irish people would eagerly embrace a stylish, glossy interiors magazine now seems a given but back in 2003, when Buchanan-Johnston first started working on the concept, many people thought it just wouldn't happen and she herself had moments of doubt. But creatively and financially, it was something she needed to do.

She started modelling when she was 14, which she loved, but knew she never wanted to do full-time, and worked for a Belfast fashion magazine before relocating to London.

After modelling and doing freelance journalism there, she took a career break and worked for Virgin Atlantic before being head-hunted by a private jet company and moving to Athens where she met her husband, who is Greek. She learned to speak the language fluently and was happily settling into Greek life when her daughter Kirsten (now 10) was born and she began to long for home.

She returned to Northern Ireland with Kirsten and applied for a job selling advertising in a magazine because an editorial position wouldn't pay enough. "There was no money. I had more or less left my husband . . . he thought I'd just gone to take a break and clear my head, " she remembers. "He wasn't really too worried but I know that if I was going to take this job, if I was going to stay here, I needed something that was really well paid."

She'd never sold advertising before and lied in the interview, landing the job. "On my first day I was sitting there in front of the phone, saying 'What am I going to say'. I was so scared! But I was so hungry to make this work that I surprised myself. Then that was another string to my bow."

Her marriage was definitely over by this stage . . . although she says she and her former husband are good friends . . . and she stayed with the company for a number of years, moving down to Dublin, where she bought a house and met her new partner, Mark.

But the realisation was dawning that she couldn't afford to work for somebody else for the rest of her life, and that if she did, she would have no quality of life. She and Mark had a son Calum, now four-and-a-half, and it was during her maternity leave, spurred on by a great sense of frustration, that she decided to leave her job and embark upon The White Book project. "I wanted to do something gorgeous where I could say 'this is what I do or this is where I work or this is what we produce'. The market was crying out for this as well, there wasn't anything like it, " she recalls.

Then literally, in the space of around four weeks, her life was turned upside down.

She and Mark broke up, due in part to the pressures of her new venture; her mother was diagnosed with Alzheimer's disease and her sister was killed in a car crash. "It was so bad, I thought, what do I do? Do I just lie down and die?" she remembers. "But I didn't have the opportunity to do that. I had two children, you sink or you swim. Looking back it was so bad, I just got this big burst of energy and determination." Essentially, she didn't have a choice and she needed to make a living. Somehow, she managed to get the book out and now, two years later, her foresight has been rewarded. "People in Ireland absolutely soak up interiors. It's nearly almost taken over from fashion, " she claims. There are big plans for the company, and she's talking about possible titles in the areas of foods and gardens. She wants to go international, which is why she called the company Montague Publications Group, starting as she intended to go on. Why Montague? "It's Romeo's surname from Romeo and Juliet, and Shakespeare in relation to a publishing company so it's all tied in. I used to live in Montague Avenue in London and I just love the name and then the dog got called Montaguef" Her own house, she describes as "modest".

"I've invested a lot in the business. It's almost a case of the cobbler doesn't mend his own shoes, " she laughs. "When I go home at night, I think God, my house should be so much better than this, so much nicer. I've seen that new chair, I should have my new chair in my house!"

It's completely white, pieces of art giving it splashes of colour and it's open-plan downstairs. When she originally started the business she thought she'd have more time to spend with the children and the freedom to take afternoons off, and while she can do so she won't.

"Because I think I've got so much to do, " she explains. "I pick up my kids at half six every night and by the time I get home and make dinnerf weekends, I'm the taxi service, running my kids to all the social gatherings and lessons and rugby and whatever else is going on. It's just packed in."

She has a horse and a half-an-hour gallop on the beach keeps her sane, but if the workload is tough, she's not complaining. "I love what we do, " she says simply. "I definitely don't do things the way it says I should in the book but I'm doing things the way I think will work and get people to love what we produce. To me that's pure indulgence."