NOEL O'Callaghan has taken over yet another section of land off Dublin's Merrion Square with the opening of his third hotel there, the Alexander.

Located just beside its two sister hotels, the Mont Clare and the Davenport, Mr O'Callaghan seems to have firmly taken hold of that part of the city.

The low profile millionaire accountant, turned property developer seems most comfortable as a hotelier. He has strong views on how the industry should be developed.

Calling for legislation to allow a gambling licence for a casino is just one of his current brainwaves. The establishment of a national conference centre is another. This theme has of course been close to Mr O'Callaghan's heart for some time. He previously toyed with building such a facility in O'Connell Street.

And curiously, for a man who has used his extensive accountancy skills to seek out lucrative investment opportunities in both the property and hotel sectors, another gripe is the current tax incentives package which is driving the development of Dublin's hotel industry.

This criticism is directed at the generous scheme whereby developers can write off 100 per cent of the capital costs over seven years. He believes this arrangement is yielding large tax benefits for wealthy individuals and banks working with the developers at the expense of the hotel industry.

Mr O'Callaghan is also concerned that the tax breaks, which injected such enthusiasm and confidence into the development of the business, may ultimately work against it.

Despite his concerns, it could be argued that he would never have gone into the hotel business but for the attractive investment schemes which were then available to fund hotel refurbishment and development.

His first foray came just over eight years ago when he bought the Mont Clare from a court appointed receiver for £400,000. In a short period he managed to completely remodel the hotel, spending millions on upgrading and expanding its rooms and facilities, through a business expansion scheme (BES).

The £2.5 million scheme, which allowed investors to claim sizeable tax relief, financed much of the Mont Clare's transformation.

Clearly happy as a hotelier, Mr O'Callaghan quickly set about opening a second hotel looking to the former Merrion Hall site across the road from the Mont Clare.

The hall, built in the 1860s by the Plymouth Brethren as a gospel hall, was destroyed in 1991 by a fire. Later that year, Mr O'Callaghan purchased the site for £1.1 million and built his second hotel, the Davenport, which retained the original facade.

The group, which employs around 350 people, has also recently expanded to include the Eliot Hotel in Gibraltar and the newly opened Alexander. The four hotels are estimated to yield a turnover of around £5 million annually.

As his hotel interests flourished, Mr O'Callaghan forged ahead with his property development ventures. One of his companies, Persian Properties, carried out most of the building work on the hotels while other projects were also continuing apace.

In marked contrast to his willingness to talk about his hotel interests, questions on his current and previous property interests are met with a stony silence. It is only with considerable effort that he discloses the name of his main property vehicle, Sherborough Securities.

The property side of his portfolio, it appears, is kept firmly low key. "We don't put up signs," he says.

One of it's most recent undertakings was the development of Dublin's Charlotte Quay to include a 210 unit apartment block. Over the years, he has built residential property schemes in Ailesbury Road and in Killiney and office blocks around the city. Despite his lowkey style, some of his developments have periodically hit the headlines.

Last year, be sold a derelict site on O'Connell Street for £1 million to Dublin businessman Richard Quirke, as a potential site for the proposed national convention centre which now seems destined for the RDS.

Mr O'Callaghan had held onto the derelict site in O'Connell Street for almost 20 years. His plans at one time for it included a hotel development to be partly funded through a BES scheme. That project was abandoned and the site was mainly used as a surface carpark.

He has also had different views with An Taisce from time to time over the proposed development of a group of buildings off St Stephen's Green which he hoped to convert into a hotel.

The buildings include the birthplace of Sir Edward Carson and that of the playwright George Fitzmaurice. These have since been designated as national monuments and, though derelict, will both have to be restored.

Mr O'Callaghan was also reluctantly dragged into the limelight two years ago when as a director of CIE he became embroiled in a board row with the then Minister for Transport, Mr Michael Lowry.

He was one of seven nonworker directors appointed by previous Fianna Fail led administrations, joining the board in 1994.

Mr O'Callaghan became one of the "famous five" group of directors at the centre of a bitter conflict with Mr Lowry. They all subsequently resigned from the company having been requested to do so by the Government.

From Kanturk in Co Cork, Mr O'Callaghan has been running his own business from the start of his career. Described as a loner, he is known to be a tough and shrewd operator.

His wife, Miriam, is a sister of another Dublin property developer, Mr John Ronan, who in the 1980s worked in partner ship with Mr O'Callaghan on several projects, but they are no longer associated.

His main interests are "bad golf and slow horses" with horses clearly attracting most of his spare time. He keeps a few horses at his farm outside Clane, Co Kildare.