This paper describes the evolution of early intervention (EI) in Catalonia until its present day. The first attempts were established in the early seventiesby interdisciplinary teams trying to improve the development of children with disabilities with an understanding that it was crucial to intervene as early as possible. Nowadays, EIin Catalonia consists of a well-established public network of Early Intervention Centres with specific catchment areas responsible for preventing, detecting, treating and monitoring children (and their families) with disorders in their development. The article provides an accurate description of the process that families with children with developmental delay follow from the time they discover a problem in their child’s development until they reach the Child Development and Early Intervention Centre. To this end, the article is divided into two parts. The first takes a brief lookat the history of the legislation regarding EI in Catalonia, while the second focuses on how the services involved were conceived and are currently organised and implemented.