Successful candidates have to get the biggest vote in a single constituency.

ECONOMIST: Britain and Europe

It hopes to do better in an election to the European Parliament next June, for which the whole country will count as a single constituency.

ECONOMIST: How much is enough?

The first round of France's two-round, single-constituency system has always been a time for voters to express discontent with impunity.

ECONOMIST: Those mutinous French

Traditional evangelicals form the party's single largest constituency.

ECONOMIST: Social conservatives after Terri Schiavo

Thus the 24-member Senate, which is elected from a single, nationwide constituency, includes several former movie stars and generals alongside the scions of the Philippines' grandest political clans.

ECONOMIST: The Philippines

In rural areas such as south Shropshire and north Herefordshire it would mean the creation of a single, very large constituency.

BBC: Boundary Commission hearings on constituency changes

This is not a single segment of society or slice of society that represents only a small constituency.

WHITEHOUSE: Press Briefing

He said first-past-the-post delivered strong, single-party government, was easy to understand and had a "strong constituency link".

BBC: AV referendum: Union stance 'depressing', says Johnson