The ADA definitions I feel are tricky for stuttering. Employers are not permitted to discriminate against persons with disabilities if the person is able to perform the job with reasonable accommodations. However, this means they ARE allowed to reject candidates if the disability would significantly impede a person's ability to perform the "essential job function". For example, if you have a job that requires running up and down stairs all day, it is OK to reject someone in a wheelchair. Oral communication is a pretty standard "essential job function", but a reasonable accommodation is just that it might take a bit longer to get a word out. But, "speed of communication" is a subjective concept. [This is a really interesting article](http://www.ada-il.org/questions/q_stuttering.php) that says employers are also **not allowed to reject candidates due to fear of adverse public reaction**. Ie, stigma. This all comes down to the comment below about it's pretty darn hard to prove you were discriminated against in something like a job interview. Personally I think the biggest issue with stuttering/disability/work is the stigma and lack of awareness. You can be an outstanding speaker and still have disfluent speech. But, many people/employers assume "Oh s/he stutters, can't put that person in a speaking role," which is ignorant. But the reasoning is more subjective (quality and impact of communication vs. can you walk up stairs or not), so it's harder to argue against it.