How do you know when your child's behavior is a cause for concern. The key is to look for patterns of behavior that include the following:

excessive arguing (especially with parents, teachers and other authorities)
outright defiance
absolute refusal to follow rules and comply with reasonable requests
unwillingness to take responsibility for behavior; blames others for his mistakes and outbursts
deliberately annoys or upsets others (you may start to wonder if your child enjoys this)
seeks revenge, rather than being reflective
when he's upset, he says mean and hurtful things
seems chronically angry and negative

If this describes your child, then he may have something called "oppositional defiant disorder". For a psychologist to diagnose this, your child must exhibit these behaviors in a number of settings—not just at home—although your family will probably bear the brunt of these unsavory experiences.