This protocol describes an adaptation of a classic sequential touching object categorisation task to assess infant attention set-shifting, suitable for ages 12–24 months. The task is conducted in a social interactive context with a parent, who scaffolds their infants’ attention shift from high-salience to low-salience dimensional properties of objects (e.g., shape vs material). This task is adapted from Ellis and Oakes (2006), where 14 month-old infants were able to flexibly attend to both shape and material. In this paper, we present a methodological innovation which permits the direct measurement of the effect of parent-child interactions on an early developing executive function skill. This novel social interactive protocol permits direct assessment of the effect of parent-child interaction on an early executive function skill, attention set-shifting.•The parental role is to scaffold a shift in their child's attention from a high salient (e.g. shape) to a low-salient (e.g. material) dimension of the stimulus set.•The protocol is suitable for infants aged between 12 and 24 months.