Although childhood discipline is an important issue for parents, this topic is seldom emphasized by family physicians during well-child examinations. Behavior problems are relatively common but frequently under-recognized by physicians. Opportunities to counsel parents about safe, effective methods of discipline are therefore missed. Discipline should be instructive and age-appropriate and should include positive reinforcement for good behavior. Punishment is only one aspect of discipline and, in order to be effective, it must be prompt, consistent, and fair. Time-out is frequently used to correct younger children, but because it is often enforced improperly, it loses its effectiveness. Corporal punishment is a controversial but common form of discipline that is less effective than some other types of punishment. Its use is linked to child and spouse abuse, as well as to future substance use, violent crime, poor self-esteem, and depression. Despite the possible negative effects of corporal punishment, it is still widely accepted in our society. Since discipline plays an important role in the social and emotional development of children, physicians should be trained to discuss this issue with parents during routine well-child examinations.