What letters are worth putting behind your name and what are better left off? Does it change for a business card or email signature? Currently, I work for an engineering firm and have my PE so I have PE behind my name. I also recently finished my MBA and am trying to decide if I should add MBA or if that is unnecessary? What if down the road I earn my PMP, is that something that should be added? If so, should I remove something else? Seems like one is enough, two is dependent on the two, and if you get to three you are becoming more of a joke to others than an inspiration.