Yes, ADHD in adults – who were not diagnosed as children – is a very real thing. The lack of a good understanding of this condition in the public at large AND within the medical and psychological communities may be one of the most frustrating aspects of having ADHD as an adult, or suspecting you may. Dr William Dodson has produced some great work – including a webinars and articles here on ADDitude – about this topic. Basically, the existing diagnostic criteria are based only on external observable behaviors of (male) children under 12, and they have no direct relationship to what adults experience internally. He also states that ADHD isn’t truly and attention deficit problem, but an attention consistency problem, which I think is spot-on. I’ve found Dodson’s work to be refreshing and ground-breaking. Have a look at these links and do a search on ADDitude for more from him.