Randomized study of 1500 cases of ADHD in children aged 3to 7 yrs. was studied and compared to age and sex matched 1500 controls attending well child clinic. The study was conducted to determine the incidence of adeno tonsillar hypertrophy, obstructive sleep apnoea, enuresis, cognitive impairment, speech and languages defects and sleep problems in these children. About 33.8% had adeno tonsillar hypertrophy vs. 11.2 % in controls, 26.4 % had obstructive sleep apnoea vs. 0.3% controls, 5.3% had Enuresis vs. 0.1% controls, 18.2% had speech and language problem vs. 1.6% in controls, 42% had cognitive difficulties vs. 4.8%, sleep disturbances in 78% Vs. 31% controls. adeno tonsillar was done in 28%, ABA was done in 93% and Medication was required in only17% cases.