The Municipal Council (de: '''Gemeinderat''', fr: '''conseil municipal''') constitutes the executive government of the City of Bern and operates as a collegiate authority. It is composed of five councillors (, ), each presiding over a directorate (de: ''Direktion'', fr: ''direction'') comprising several departments and bureaus. The president of the executive department acts as mayor (de: ''Stadtpräsident'', fr: ''Le Maire''). In the mandate period 2017–2020 (''Legislatur'') the Municipal Council is presided by ''Stadtpräsident'' Alec von Graffenried. Departmental tasks, coordination measures and implementation of laws decreed by the City Council are carried by the Municipal Council. The regular election of the Municipal Council by any inhabitant valid to vote is held every four years. Any resident of Bern allowed to vote can be elected as a member of the Municipal Council. Contrary to most other municipalities, the executive government in Berne is selected by means of a system of Proporz. The mayor is elected as such as well by public election while the heads of the other directorates are assigned by the collegiate. The executive body holds its meetings in the Erlacherhof, built by architect Albrecht Stürler after 1747.