Methods: This study was conducted among secondary school students in two districts in Selangor Malaysia, during July 2005 until August 2006. Upon screening, 346 students were randomly assigned into intervention group (IG) (n=158) and non intervention group (NIG) (n=188). IG underwent structured group counseling regularly for four months, while no group counseling was given to the NIG but subjected to the regular smoking cessation activities organized by their respective schools. Knowledge and attitude towards smoking and quit rate were measured in both groups before intervention, and at 4, 8, and 12 months after intervention