Attention deficit hyperactivity disorder (ADHD) is a chronic developmental disorder with symptoms of inattention, impulsivity and hyperactivity. The developmental course of the disorder shows that symptoms may be present even from infancy. The aetiology of the disorder may result from many factors, genetic and neurological playing the leading role. Studies have shown that ADHD can coexist with other disorders, mainly learning difficulties. This case study concentrates on a Year 4 pupil of a Greek primary mainstream school, who displayed symptoms of ADHD (hyperactivity and impulsivity) that affected greatly his behaviour inside and out of the classroom, as well as his academic performance (learning difficulties). An Individual Educational Plan was structured by the class teacher and targeted his behaviour. The findings showed that high levels of appropriate behaviours were achieved by the creation of conditions inside the classroom that enforced these forms of acceptable behaviour. Furthermore, a significant reduction in hyperactivity and impulsivity was observed. [Paper presented at the Inclusive and Supportive Education IV Conference Congresso Internacional da Pró-Inclusão (8th, Lisbon, Portugal, July 26-29, 2016).]