THE referendum result was not the end of the play. It was just the dramatic flourish at the end of Act I. After a few days rest, Northern Ireland's word-weary politicians will be back on stage for Act II - the elections to the assembly.

In a month's time, the electors will have to choose the 108 people who can either make the new structures work or strangle them at birth. If there is no major shift in loyalties from recent Northern Ireland elections the new body will have a clear unionist majority: 56 compared to the nationalists' 44, with the Alliance in the centre having eight seats.

With the two main architects of the Good Friday agreement - David Trimble and John Hume - commanding 54 seats between them, and with the Alliance and the Progressive Unionists committed to making the new structures work, there would appear to be no obstacle to electing an executive, deciding operating procedures, and getting on with the work.

However, there is one potentially fatal weakness in the system, which explains why the No campaigners are downhearted but not despondent. The Good Friday deal contains two rules designed to ensure that any major decisions made by the assembly have broad cross-community support.

On entering the assembly every party must declare itself ''Unionist'', ''Nationalist'' or ''Other''. While the routine work of the assembly will be conducted on the basis of simple majorities of members voting, important or contentious issues must pass the special test of being acceptable to both sides. To pass, a decision must be supported by either a majority of unionists and a majority of nationalists taken separately, or by 60% of all members plus at least 40% of each ethnic block taken separately.

This is why the No campaigners remain hopeful. Ian Paisley and Robert McCartney should have 25 of the 56 unionist votes. If they can get nine of Trimble's Ulster Unionists to back them, they will be able to prevent the assembly operating. There will be no election of office bearers, no executive, no agenda for the new cross-border bodies, no nothing.

Unlike New Labour, the Ulster Unionist party is rather old-fashioned in its commitment to local democracy. Its candidates will be nominated by each local constituency association. Although Trimble can try to persuade the associations to nominate only people committed to making the assembly work, he has no power of veto. A majority of his Westminster MPs are against him. Most of them have been in their seats for two decades. The odds are good that Willie Ross in East Londonderry, for example, will be able to get some No men on the slate.

Furthermore, unlike the ''additional member'' PR system which we will use for the Scottish Parliament, Northern Ireland uses a ''single transferable vote'' system.

As Jennifer Aniston, of Friends and the shampoo adverts says, here comes the science bit. A loyal Ulster Unionist in East Belfast would normally vote one and two for two Ulster Unionists and maybe put the Alliance party as three. When the most popular candidate gets enough votes to pass the hurdle for election (which is the total number of votes cast divided by the number of candidates) the ''spare'' votes are distributed to the other candidates in the order of the voter's preference. If on any subsequent count, no candidate reaches the threshold, the one with the lowest number of votes is eliminated and his votes are redistributed to the second preference and so on until enough candidates pass the threshold to fill the six seats in the constituency.

In such a system (and this is the point of it) a candidate can be seventh or eighth after the first count but still get elected ahead of someone who initially gets more first preferences because he is the second or third choice of more people.

This is where Paisley's single-mindedness becomes an advantage. The No alliance should exceed the estimated DUP vote because it will encourage cross-party support for No candidates. The best way to counter this would be for moderate nationalists who vote SDLP to put Trimble's Yes unionists down as their second and third preferences but such cross-confessional voting is unlikely.

If you are still following this, you can see why the size of the Yes vote in the referendum was vital. Gerry Adams was utterly wrong when he said that ''50% plus one is enough'' - it never would have been. Trimble had to get a big enough Yes vote to pull up those waverers among his activists and to make sure that his voters do not leak second and third preferences to the No camp.

Even if Trimble can do well enough to prevent the DUP wrecking the assembly he has a second hurdle to cross. If the No unionists refuse to vote for him he could well lose his rightful place as First Minister to John Hume. In the interests of long-term stability, John Hume might well refuse to run against Trimble and accept the post of Second Minister. Now that would be an encouraging sign.

There is a very long way to go. At some point Sinn Fein and the IRA will have to convince the doubters that the war really is over. But the near unanimous result in the Irish Republic gives Adams the mandate he needs. The IRA claims to embody the will of the Irish people. Well, the Irish people have spoken.

Given the nature of much political decision-making in the North, the fact that nationalists liked the Good Friday agreement was bound to make a lot of unionists dislike it. But the 70% Yes in Northern Ireland almost certainly means that a majority of unionists voted for the settlement. That endorsement should allow Trimble to regain the loyalty of enough of his party to see him through the next stages.

Now, if members of the audience would like to finish their ice-creams and return to their seats, Act II will begin.