Member of the National Assembly for Wales

The National Assembly for Wales is composed of 60 members known as AMs or Assembly Members (in Welsh: ACau or Aelodau'r Cynulliad). Forty are chosen to represent each individual constituency, and 20 are chosen to represent the five regions of Wales.

Each person in Wales is represented by five AMs – one AM for their constituency (the local area in which they live), and another four AMs covering their region. Wales' five regions are: Mid and West Wales, North Wales, South Wales Central, South Wales East and South Wales West.

AMs are elected in one of two ways:

Forty are elected as constituency AMs and twenty are elected as additional members, four from each of five regional groups of constituencies. This additional member system produces a form of proportional representation for each region.

All AMs positions become simultaneously vacant for elections held on a four-year cycle. If a vacancy arises at another time, due to death or resignation, then it may be filled in one of two ways, depending of whether the vacancy is for a first-past-the-post constituency AM or for an additional-member AM.

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