Attention deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that often persists into adulthood, affecting approximately 1.5% - 3% of the adult population in Portugal. Untreated ADHD in adults is associated with increased risks of substance abuse, criminality, poor academic and professional performance. Less than 20% of adults with ADHD are properly diagnosed and treated due to overlapping symptoms with other psychopathological comorbidities, lack of awareness, and prejudice surrounding this disorder. This position paper results from expert meetings involving six Portuguese experts in managing adult ADHD. It aims to guide diagnostic and treatment strategies, as well as address the main barriers and limitations in managing these patients within the Portuguese context, specifically regarding diagnosis and treatment. Furthermore, it seeks to clarify and demystify associated misconceptions, increase medical awareness, and promote discussion for the development of guidelines to improve the diagnosis, treatment, and quality of life of adults with ADHD in Portugal.