Barcelona’s city council is comprised of sectors, the political branch and the administrative branch. The political branch is currently headed by Jordi Hereu, the sitting mayor of Barcelona, who took office in September 2006. The political branch includes elected officials (including 17 councillors under the mayor) and those who can take decisive and informative action, while the administrative branch serves to execute and manage the decisions and programmes created by the political branch. The Ajuntament building (City Hall) is located in Plaça Jaume, and is open for guided tours on Sundays. Parts of the building date back as far as the 15th century (the side entrance) and the 18th century (the main façade).