Professionalism

No matter the situation, you must always remember to maintain a certain level of professionalism.

But he yelled first. But he cut me off. But she was rude. But he cursed first.

C'mon, are we still 10 years old? A true professional, not an occassional professional, never "stoops" to the other person's level. Take a deep breath and let the moment pass. You will be happy you did.