so there are 3 things really here. 1. the first is how you personally should react when the person stutters. I would say, if its mild- moderate- as in its noticeable but does not lead to a break down in communication- give them all the time they need to get through it. Try to maintain eye contact and just wait it out. It doesn't take that long in the grand scheme of things and interrupting or distracting will actually make it take longer. Also just slowing down your own speech a little bit may help just slow down the pace of the convo which may very well help. I don't mean "ssssloooow mooootiiiooonnn", just a few more pauses and slightly slower pace. 2. If its severe or profound and is inhibiting your and their ability to communicate, then you 100% need to address it respectfully. Ask the person what you can do to help, what they prefer you do. Just so you know, there is really not much you can do to "help" but by asking, you lift the veil of fear, shame, and anxiety for the person and really lay a firm foundation for a good relationship and good communication. I would say something like "I've noticed you stutter **a little**. I dont know much about it but I would like learn more about it if you are willing to tell me. I want to know how best to facilitate our communication." And then listen. there are so many people here say that disclosure that they stutter is the single best thing you can do to have better speech. If he won't disclose, you do it. 3. How to deal with the co-workers? You know your group. I used to work in a team of the rowdiest ER nurses and docs on earth and they were predators- they would pick on and tease people mercilessly- it was like a hazing ritual. Some people developed a thick skin, some people quit. It was tough neighborhood. Again, I would brooch this topic once you were talking about it (in section 2) and ask them how they would like you to handle it. They may be like- "nah I got this, I can throw down with the best of them" or they may say "go ahead and tell them so that I don't have a problem." Ultimately, you know your people. I hope this helps. ps- on the helping with the word or making light of it... I would not do that unless the Person who stutters **specifically says they are OK with this**. BTW, are you going to inadvertently do some cringe shit?- of course. But as soon as it happens, apologize. My *husband* does cringe stuff even now, he mocked me once jokingly in front of our friends. It was a big big big fight. He apologized immediately, but it really hit my self-confidence for a few days.