Clinicians face challenges in distinguishing Attention-Deficit/Hyperactivity Disorder (ADHD) from higher-functioning autism (HFA) due to overlapping symptoms and behavioral patterns. Understanding the nuanced differences is crucial for accurate diagnosis and effective interventions. Both conditions present a significant symptom overlap, making it difficult to distinguish them, particularly when they co-occur. ADHD is associated with inattention, hyperactivity, and impulsivity, while HFA involves intense focus on specific subjects, pragmatic communication difficulties, and literal thinking. A comprehensive evaluation, involving interviews, standardized tools, and collaborative expertise, is necessary to differentiate and accurately assess individuals. Case studies emphasize the need for innovative and flexible diagnostic approaches. Acknowledging individual variability, professionals must be adaptable, prioritizing accurate, inclusive assessments that reflect personal narratives and neurodiversity, and ultimately guiding tailored support strategies.