Last night I was chatting to a Black police officer, and somehow we got onto the topic of accents. He said that at work, he was very aware of his Asian accent and did his best to adopt a Queen’s English accent so as to not alienate himself from the people to whom he talked (mainly white people). According to him, speaking in a "foreign" accent could create a barrier between him and his interlocutor and make his work less efficient.
I knew exactly what he meant when he said that the way you talk greatly affects your working relationships. When I’m interpreting, I’m very careful to disguise my Southern French accent and speak in a neutral "Parisian" way. I think the job of an interpreter is to convey messages as faithfully and neutrally as possible and not to attract attention to oneself. Speaking with a strong accent is a sure way to distract people’s attention from what you are saying to how you’re saying it, as it puts the limelight on you and not on the information you’re trying to communicate. When I let a vowel slip, I invariably notice that the person I am talking to suddenly has a little smile; I know that they are probably wondering where I am from in the South instead of concentrating on what I am saying to them.