--- - |2 Abstract Throughout life, actions and language are inherent to social interactions. A long‐standing research question in cognitive neuroscience concerns the interrelation between verbal and non‐verbal forms of social interactions, that is, language and action. Perceiving how actions are performed and why they are performed in a certain way is crucial for the observer to anticipate the actor’s goal and to prepare an appropriate response. It is suggested that predicting upcoming events in a given action sequence can be compared to the way we process the language information flow. Goal‐directed actions can be sequenced in small units, which are organized according to a hierarchical plan, resembling the hierarchical organization of language. Research on adults suggests that manipulating the action structure (i.e., action syntax) leads to analogous cortical signatures as a similar manipulation of a sentence structure (i.e., language syntax). Whereas in adults language and action knowledge are based on life‐time experience, in infants both domains are still developing. The current study examined the neural processing of structural violations of observed goal‐directed action sequences in infants at 6–7 months, using event‐related potentials (ERPs). Results showed that a structural violation of the action sequence elicited bilateral frontal positivity effects. This suggests that infants capture structural regularities, and it adds a crucial element to the understanding of general syntactic regularities and their violation from an ontogenetic perspective. - Developmental Science, Volume 21, Issue 6, November 2018.