This was a collaborative action research study by lead staff, researchers and parents at the Pen Green Centre for Children and their Families in England. The study focuses on the factors enabling access to children's services by nine parents from challenging family contexts. The critical questions were: What enabled some parents to overcome potential barriers (e.g. gender, ethnicity, language, additional needs) and to access services for their children? What was it about them personally? What was it about the Centre? And what was it about the relationship between them and the Centre that enabled access to be sustained? Using the parents' own words, a grounded theory on the nature of access to early childhood services within a children's centre was developed. It is described as the "architecture of access." (Contains 1 table, 1 figure, and 2 notes.)