Stuttering and stammering since childhood. Went to a speech therapist when I was a teenager and it did help a bit, but it hasn't gone out completely. I still do it multiple times a day. As others have pointed out, phone calls, interviews and presentations are the worst. It was a huge psychological block when growing up, especially talking to girls.

What worked for me was that I read a lot. And it opened my mind. I realized that if you are good at something, and if you can excel at it and provide something of value to someone, you are going to do well in life. Also I realized that due to my speech problems, there are somethings that I may never be able to become or achieve, like a smooth talker. So I decided pretty early on, that I need to focus on my strengths and make them so awesome that my limitations are overshadowed by them.

Since I can't talk much without stuttering or stammering, I keep quiet most of the times. This has mostly led people around me to believe that I am a reticent guy who keeps his focus on the work before him. Another thing that I do is not open my mouth until I have something really concrete to say. The argument that I am going to put out, is par often well thought out, so that I don't have get into a talking situation with someone.

Even taking interviews is a tough task.

All in all, it hasn't turned out as bad as I thought. Life is still good. :)