The Liberal Democrat conference is usually a mere prelude for the main events held by Labour and the Conservatives.

But when delegates assemble this weekend for their meeting at the Brighton Centre, they could be forgiven for thinking it will be something better than that.

Liberal Democrats scored well in the May local elections, taking almost one-third of the vote, and are running at 20 per cent in the opinion polls.

There are signs their candidate, Sarah Teather, will do well and could even win the Brent East by-election tomorrow.

With Labour losing its gloss and the Tories making little headway, there is a real chance the Lib Dems could get power of a kind they have not seen for 80 years.

With that power must come responsibility. A party without prospects cannot afford to be all things to all men and women.

A party pushing to play its part in Government will need to have its policies and personalities tested to see if they are up to the mark.

This process can start taking place at Brighton if the Lib Dems use their conference as a real debating chamber and not as the showpiece the Labour and Tories conferences have largely become.

There are major issues to be discussed next week, such as Iraq, public services and Britain in Europe, where the Lib Dems can take the lead. If they miss this opportunity, they deserve to sink back into third place.