Assertiveness is the quality of being self-assured and confident without being aggressive. In the field of psychology and psychotherapy, it is a learnable skill and mode of communication. Dorland's Medical Dictionary defines assertiveness as:

a form of behavior characterized by a confident declaration or affirmation of a statement without need of proof; this affirms the person's rights or point of view without either aggressively threatening the rights of another (assuming a position of dominance) or submissively permitting another to ignore or deny one's rights or point of view.