It was the stay-at-home slacker's channel of choice, with Judge Judy, Sunset Beach and Jerry Springer keeping many a student out of the lecture halls.

The only problem was that hardly anybody else tuned in to TV3 circa 1999 and RTÉ executives routinely poured scorn on a station that relied on cheap and cheerful foreign imports to fill its schedule.

Fast forward to 2010 and things have changed utterly. In a moment of panic last week, RTÉ was forced to put Pat Kenny's Frontline head-to-head with the phenomenally popular The Apprentice because the state broadcaster was getting the socks knocked off it each Monday. But more than 507,000 people still tuned into the boardroom reality TV show. TV3 continues to own the audiences on Monday nights and is quickly eroding RTÉ's traditional TV monopoly. It is set to inflict further damage over the next few months with The X Factor pulling in once unimaginable figures each Saturday.

So how did they do it?

The main figure credited with pulling the once maligned station out of the dark ages is Ben Frow, TV3 director of programming and a former senior executive at Channel 4, who unleashed Gok Wan on an unsuspecting public.

Frow, with a small team of mainly Irish talent, concentrated on transforming TV3 into a genuine rival for RTÉ.

"When I first came in three years ago, the station was very reliant on acquisitions and took a lot of programmes from ITV and other channels. There were very few home-produced shows and we had the reputation of having a very loyal, heavy and concentrated audience of a certain age, a fact which advertisers struggled with.

"When I came along we made a conscious decision to turn things around and we started by creating Irish-produced programmes and we brought in young and very talented people."

Frow said the station only reached a turning point in March 2009.

"Things started fitting together that March when we found the winning formula. I would sit down and watch TV like a viewer, not like a TV executive. We started to realise that viewers wanted programmes like The X Factor, Glee, and The Apprentice, as well as Irish productions about crime and current affairs. Then we maximised our in-house talent with people like Vincent Browne and Colette Fitzpatrick.

"Now it feels like things have finally come together and have finally gelled".

Advertisers agree, saying the station is now most attractive to advertise with ? bad news for RTÉ.

"The station is attracting a new, younger audience with shows like The Apprentice and this is very welcome news for advertisers who want to hit that younger demographic," said Tommy MacDonnell, director of Ogilvy, one of Ireland's biggest advertising companies.

"They are generating noise with a lot of press coverage and social media coverage and it goes to show that they are leading the way because viewership is not the only currency when it comes to advertisers now."

MacDonnell said TV3 was surpassing its competition when it came to reeling in the advertisers.

"Their main competitor is RTÉ which is funded by licence fee and advertising. But TV3 will move ahead because it is fast-paced while RTÉ is slower moving, and this is now what is setting them apart. We want that sense of energy."

According to Frow, part of the station's continuing success is down to exactly this: the ability to turn around and broadcast programmes with minimal waste and at maximum speed.

"There have been budget restrictions in the station, but it has actually worked to our advantage. There is no room for waste in here and it makes things so much simpler. I have worked in TV stations where I would give out €30,000 for someone to make a programme and it would never see the light of day, and that was happening all the time. Everything in here so is carefully thought out, and very precisely executed."

Frow said that while he has been criticised as being "too crime heavy", documentaries like Gangland Ireland and Ireland's Costa Criminals have proved popular with viewers and he plans to continue that success with shows such as Cocaine Wars and 24 Hours to Murder heavily promoted at the recent autumn schedule launch.

Thursday evenings are now dedicated to true-crime documentaries while Tuesday nights sees live Champions League football. Old favourites such as Coronation Street and Emmerdale continue to draw huge figures.

Last week may well have seen a transformation in the hierarchy of television in Ireland. TV3 became the number one channel in the country last Saturday when The X Factor, with over 751,000 tuning in, trounced the ratings of even RTÉ's The Late Late Show on the previous night.

Furthermore, the station's flagship entertainment programme, The Apprentice, has not only trodden all over RTÉ's current affairs programme Frontline but has outdone the viewing figures of RTÉ's Nine O'Clock News.

An episode of Ireland's Greatest, hosted by Miriam O'Callaghan, is also thought to have suffered a ratings hit due to the time change.

An RTE spokesman said "Given the special nature of these Frontline programmes, at this unprecedented time in our economic history, we believe that the audience appetite is best served with this subject matter directly after the Nine O'Clock News.

"We regret if any fans of the series missed the programme due to the time change. The Frontline and Ireland's Greatest are entirely different propositions to The Apprentice."

Bob Hughes, deputy director of news with TV3, said his station's current affairs was going from strength to strength, despite the odd controversy.

Its news coverage came in for serious criticism over the handling of a report by political editor Ursula Halligan last St Stephen's Day when she announced that finance minister Brian Lenihan had been diagnosed with pancreatic cancer. The Broadcasting Authority of Ireland received 88 complaints over the report.

Halligan was also the first to question Brian Cowen last month over his infamous Morning Ireland interview when she told him: "Radio programmes and the internet are alive with the belief that you were either drunk or hungover on the Morning Ireland interview."

According to Hughes, "the Irish public want to hear about the main stories and be informed, in a way which is not condescending but instead intelligent and conversational."

Meanwhile, Frow said he was determined to keep the station on an upward trajectory. "RTÉ is having a good autumn but it is a long game we play in TV3. Our programmes are up year-on-year and that is because we are constantly adapting to a changing audience. We had a tough time in the past, but we are holding our own and are not going to rest on our laurels. The job is never done."