In 1995, the City Council adopted the Aalborg Charter, the first step towards the creation of a local Agenda 21. After an intensive participatory process, Barcelona specified the details of its Agenda 21 in the Citizen Commitment to Sustainability, a document drafted by broad consensus that defined goals and lines of action for the 2002-2012 period. In December 2012, the organisations reaffirmed their commitment to the values of the Citizen Commitment for Sustainability 2012-2022.

The approval of the Government Measure for the Greening of Council Services (2001) led to the creation of the Green Office Programme and the publication of the Green Office Guide.