On the surface, Fianna Fail and the Progressive Democrats are working well together: the parties have just published a revised Programme for Government; Bertie Ahern and Mary Harney lead the political beauty contest in terms of satisfaction ratings; and support for their parties is holding up. But behind the scenes, the coalition arrangement is under tremendous pressure.

The latest Irish Times/MRBI opinion poll shows the Government's satisfaction rating to be at its lowest level since the coalition was formed in 1997. Worse than that, its harshest critics are found amongst supporters of the Progressive Democrats, where 63 per cent declare themselves to be dissatisfied. By contrast, 57 per cent of Fine Gael supporters and 55 per cent of Labour Party followers are unhappy. And the figure drops to 30 per cent among Fianna Fail supporters.

The sudden lurch in public opinion has been building for some time. It was fuelled by the various tribunals, dishonesty in politics and disclosures about widespread tax evasion at the Dail Committee on Public Accounts. But healthcare, the nurses' strike and remuneration for politicians all played their part.

The precipitous drop of 12 points in the Government's satisfaction rating since last June, when the State prepared to vote in the European and local elections, will come as balm to Fine Gael and the Labour Party, whose candidates failed to make the hoped-for breakthroughs in those elections. Those most likely to vote - the over-50s - are most dissatisfied. And the fact that people moved directly from satisfaction to dissatisfaction, without any interim phase, will encourage a more combative approach by the Opposition parties. ail.

The concern of the Progressive Democrats - or what Fianna Fail might regard as their dog-in-the-manger attitude to coalition - is hardly a recipe for solidarity. And Mary Harney has made it clear on more than one occasion that she will not stay in Government if she is misled, or proper standards are not applied.

Apart from the sudden drop in Government support, a remarkable consistency has informed the public's reaction to party leaders since last June. Satisfaction with Bertie Ahern has risen marginally, from 67 to 69 per cent; Mary Harney's rating remains the same at 61 per cent; John Bruton has gained four points to 47 per cent and Ruairi Quinn has dropped a point to 51 per cent.

Support levels for political parties in that June poll were not directly comparable to other surveys because of the order in which questions were asked. Even allowing for that, the Labour Party and the Progressive Democrats will be reassured by the recovery in their support base.

GIVEN the sharp fall in support for the Government, Fianna Fail will be pleased at the showing of 47 per cent for the party, down four points from an upsurge in June. Support for Fine Gael has drifted by two points and now stands at 23 per cent. The Labour Party has moved from 11 to 14 per cent. The Progressive Democrats have put on two points to 4 per cent. Sinn Fein has added a single point to 4 per cent. The Green Party has dropped two points to 2 per cent. And the Workers' Party remains unchanged at 1 per cent.

Support for Fianna Fail is invariably overstated for a variety of reasons. And while the party scored 51 per cent in the mid-election June poll, its actual vote in both the local and European elections was slightly less than 39 per cent. Figures like that offer comfort to the Opposition parties and, according to a new adjustment model devised by MRBI, the gap between the combined support of Fianna Fail/Progressive Democrats and Fine Gael/ Labour would be only three points, with Sinn Fein, the Green Party, the Socialist Party and Independents holding the balance of power.

Dublin has been the cockpit of political change in the past, with trends showing there first. In that regard, Sinn Fein is now attracting 6 per cent of the vote in the capital, compared to 5 per cent for the Progressive Democrats. Fianna Fail takes 42 per cent, compared to 19 per cent for Fine Gael and 18 per cent for the Labour Party.

If the attitudes of young voters are an indication of tomorrow's governments, then Fianna Fail has much to be happy about. In the 18 to 24 age group, Fianna Fail attracts 58 per cent support, compared to 18 per cent for Fine Gael; 9 per cent for the Labour Party and 8 per cent for Sinn Fein.

The public seems to be going off the Government, without having made up its mind about an alternative.