Fetal alcohol spectrum disorder (FASD) is one of the leading causes of intellectual disabilities. Self-regulation in FASD is poorly defined and interpreted in varying ways, making informed clinical decision making difficult. The objective is to operationally define self-regulation in the FASD population using the Walker and Avant (2005) methodology to inform clinical decision making, and self regulation assessment and interventions for people with FASD. The results of our analysis suggest that, in relation to FASD, attentiveness, thoughtful & deliberate actions, calm & collected behaviors, inhibition, and emotional regulation are the defining attributes of self-regulation; resulting in an operational definition that is unique to this population.