mixed member proportional (MMP)

The mixed member proportional (MMP) system is a mixed system of representation which usually combines a single member plurality electoral system with a list system of proportional representation to achieve an assembly whose party composition reflects the proportion of votes cast for each party.  Voters are required to vote for both their choice of local member , and a preferred party (sometimes this is combined into a single choice for a candidate and party), and the assembly is made up of members who are elected from single member electoral districts and members who are elected from party lists.

This system has been adopted for the German lower house (the Bundestag) and, more recently, by New Zealand’s House of Representatives.  This mixed system aims to combine the advantages of geographical representation (with a local member) with the proportional representation of parties.