On the pioneering ecological urban strategies of a Spanish public consortiumBCNecologia (the Urban Ecology Agency of Barcelona) is a public consortium consisting of the City Council of Barcelona, the Municipal Council and Metropolitan Area of Barcelona and the Barcelona Provincial Council. BCNecologia has played a key role in defining a new urban model for Barcelona--a model that has placed the city at the forefront of worldwide urban transformations--by designing a superblock and orthogonal bus network strategy for the Catalan capital. BCNecologia: 20 years of the Urban Ecology Agency of Barcelona looks back at over 100 projects carried out by the Agency in cities across the world. These studies are presented through a tree with five themed branches that describe various sustainability indicators, superblock-based urban regeneration plans, new mobility and public space planning models, and environmental and circular economy-oriented proposals.