Several studies have shown an association between retention of various primitive reflexes, such as Moro, asymmetrical tonic neck reflex (ATNR), symmetrical tonic neck reflex (STNR) and tonic labyrinthine reflex (TLR) and attention deficit & hyperactivity disorder (ADHD) symptoms. The Moro reflex has been suggested as a gateway reflex for other reflexes, and its association with the Polyvagal theory may serve as an explanation for several of the symptoms associated with ADHD. ATNR, STNR and TLR have been linked to not only presence of symptoms, but also to their severity. Other Reflexes such as the palmar and plantar grasp may explain some of the sensory difficulties we see with ADHD children, and the comorbidity of nocturnal enuresis (NE) may be associated with the spinal Galant and/or Perez reflexes. While the main purpose of this paper is to discuss ADHD, it is important to remember that retained primitive reflexes has also been associated with other developmental disorders, which can be present as comorbidities with ADHD, such as autism spectrum disorder (ASD), dyslexia, developmental coordination disorder (DCD) and others. Based on existing literature, we suggest that screening for primitive reflexes may serve as an early detection tool for ADHD, and other developmental disorders, and examine the possibility that therapies that include primitive reflexes integration may serve as a possible cost-effective early intervention for ADHD and other developmental disorders, thus reducing severity of symptoms, cost of treatment and special education needs and improving quality of life in children with ADHD and their families.