Self-assured diplomacy is a term that refers to the skill of handling difficult situations with confidence and composure while promoting oneself or one's cause. Other synonyms for this term include confident negotiation, assured diplomacy, and assertive communication. These words all carry the connotation of a person who is in control and able to navigate complex situations with ease. Other words that might be used to describe this same skill set include tactful negotiation, smooth diplomacy, and shrewd communication. All of these synonyms reflect the importance of possessing confidence and poise in high-pressure situations when it comes to international relations and negotiating.