Assertive discipline is a structured classroom management system emphasizing positive behavior strategies over dictatorial approaches. The theory, proposed by Canter, establishes clear boundaries for student behavior and underscores the rights of both students and teachers to a conducive learning environment, along with the importance of proactive discipline and trust-building relationships. Key features include the necessity of firm consequences for misbehavior, positive reinforcement for good behavior, and the teacher's responsibility to model appropriate conduct.