Three single participant studies examined effects of in-home parent-implemented Positive Behaviour Support (PBS) interventions on behaviour of individuals with brain injuries. Parental and independent observations of morning routine behaviour or problem behaviour (viz., noncompliance during meals or morning routines, yelling, kicking, swearing, and so on) were taken during baselines and PBS interventions, which consisted of person-centred functional assessments of behaviour, emphasis on changing behavioural antecedents, parent participation in assessing, treating, and evaluating behaviour change, and in-home parent coaching and support. Results show decreased problem behaviour or improved morning routine behaviour, which corroborate and add to the few studies that applied similar parent-implemented interventions. Future comparative studies between PBS and out-patient interventions are indicated.