Persons with intellectual disability commonly present to healthcare professionals with behaviours of concern, which has significant impact on their quality of life, as well as that of their caregivers. These behaviours often result from a combination of complex factors, which includes physical and mental health conditions, psycho-emotional issues, and social-environmental difficulties, all of which are made more challenging by their inherent cognitive and communication difficulties. A comprehensive assessment is essential and the objective will be to determine the underlying reason(s) for the behaviour. Depending on the underlying cause(s) ascertained, pharmacological and/or non-pharmacological treatment will have to be implemented promptly and appropriately in a person-centred manner. It is elucidation of the underlying cause(s) and the various contributing factors that may pose significant challenges for primary care physicians due to limited time, resources, and training. This article aims to propose a practical approach to assessing and managing behaviours in the primary care setting.