This review integrates and evaluates research conducted on possible contributing factors to peer relationship problems of children with attention deficit/hyperactivity disorder (AD/HD). Substantial evidence suggests that children with AD/HD have serious problems in multiple aspects of their relationships with peers. Difficulties resulting from inattention, impulsivity, and over activity negatively affect these children's performance in the peer group and as a result, children with the disorder are often rated as less popular and more rejected by their non-AD/HD peers. This article critically reviews risk factors for peer relationship problems of children with AD/HD including family, school, and child-specific factors. The implications of AD/HD research are examined with an emphasis on developing an ecological perspective to addressing the peer relationship problems of children with the disorder.