Variability in decision-making with regard to child protection is gaining traction in social work. This article presents the findings of a quantitative study carried out with child protection professionals in the Basque Country. The goal is to analyse variability in decision-making for child protection based on the personal characteristics of the professionals involved in such cases. Using a vignette methodology, the study explored whether the decision to keep a child with his family or separate him from them is related to socio-demographic and experience-based variables, and also to education and professional experience. Based on the hypothesis that there is variability among professionals when deciding whether to implement a family preservation or separation decision, this study has found significant differences in the decision based on professional experience, the age of professionals and whether or not they are a parent. For other variables, the results indicate that different factors are important, such as the organisational context in which professionals work.