Transactional analysis can provide a scientific basis for modifying teacher behavior. Three ego states, parent, adult, and child, exist in all people at all times. It is the verbal and physical interplay among these states that can be observed in behavior patterns. The parent ego state asserts value judgments and classifies behavior as good or bad. The adult ego state is intelligent, organized, curious, and adaptable. The child ego state contains the impulses that come naturally to infants and is full of emotion. If social transaction is parallel (between people having equal ego states), it is complementary and can continue indefinitely. Crossed transactions, which occur between people having different ego states, are the source of communication problems. Ulterior transaction occurs when communication exists at both the overt and the covert levels. Teachers can relate to and teach students better by adopting an appropriate ego state at any given transaction. Analysis of teachers' responses to classroom situations shows the interaction between the teachers' and the students' ego states. Knowledge of transactional analysis would form a useful part of both preservice and inservice teacher education programs. (FG)