An alderman is a member of a municipal assembly or council in many jurisdictions founded upon English law. The term may be titular, denoting a high-ranking member of a borough or county council, a council member chosen by the elected members themselves rather than by popular vote, or a council member elected by voters.

The title is derived from the Old English title of ealdorman, literally meaning "elder man", and was used by the chief nobles presiding over shires.

Many local government bodies used the term "alderman" in Australia. As in the way local councils have been modernised in the United Kingdom and Ireland, the term alderman has been discontinued in a number of places. For example, in the State of Queensland before 1994, rural "shires" elected "councillors" and a "chairman", while "cities" elected a "mayor" and "aldermen". Since 1994, all local and regional government areas in Queensland elect a "mayor" and "councillors." (The Brisbane City Council has always had a "Lord Mayor"). An example of the use of the term alderman was in the City of Adelaide. Aldermen were elected from the electors in all the wards.