In recent years, there has been increased clinical demand for assessment and management of adults presenting with inattention and hyperactivity. It has been previously argued that diagnosing attention-deficit hyperactivity disorder (ADHD) in adults is challenging for multiple reasons, including the risk of recall bias, reliability of collaborative information, the age and gender-specific issues as well as psychiatric comorbidities (Suetani et al., 2023). Compounding these, there remains uncertainty if late-onset ADHD is different to childhood-onset ADHD identified in adulthood. In this brief communication, we summarise the findings from two recent reviews on this topic and suggest potential future directions.