The country is divided into regions with individual constituencies within each region.
Each voter has two votes: one for their constituency MP and one for a party in the region.
Within constituencies, voters elect individual representatives using FPTP.
Within regions, voters elect additional representatives (known as a “top up”) according to a vote using LPR.
MMP is in use for Scotland Parliamentary elections and for elections to the Greater London Assembly. It was also used for the Welsh Senedd but has now been rejected in favour of LPR.