The Irish telecommunications sector has changed out of all recognition in recent years. And events over the past week show that it is still developing rapidly.

First came the successful flotation of Esat Telecom on the Nasdaq, which should underpin the finances of the fast-growing group for a prolonged period and provide it with the funds it needs to both develop its own network and to contribute to the development of Esat Digifone, the mobile phone operator in which it holds 45 per cent.

The levels of investment required over the next few years are enormous, but Esat and its investors will hope that by getting the mix right the returns will be handsome. And in a local move, Esat is moving more heavily into the Internet through its purchase of provider EUnet.

On the home front, Sean Melly's TCL Telecom got a boost as its parent WorldCom - which recently bought out the Irish company for an undisclosed sum - won the race for MCI. By linking it in to this major international alliance, the move should allow TCL to develop into a bigger force in serving the corporate sector.

As if to illustrate the potential, WorldCom announced this week that Ulster Bank was the first corporate to connect to its alternative fibre network, offering links from the IFSC to financial centres throughout the world. Dublin is the 87th city in the world in which WorldCom has made this investment.

Meanwhile, British Telecom's international strategy is now in serious question. It lost out in the race for MCI and while its joint venture, Concert, - formed with MCI to serve major multinational corporates - remains, its goal of building on this through a full-scale alliance will not now be realised.

For Irish corporate customers the benefits of the liberalisation of competition are thus flowing through already and competition for their business is set to intensify. For policymakers, the question now is why Ireland - which is marketing itself as a progressive economy - has a derogation which will allow it to delay full competition for the business of domestic customers until 2000.