Attention deficit hyperactivity disorder (ADHD) is one of the most feared and misunderstood of all medical conditions. Despite over 200 scientific papers being published on this neurological condition every year, it remains stigmatised and controversial. Some doctors don't even believe it exists.Yet it is estimated that as many as 3-5% of the childhood population, and over one million adults in the UK are affected by ADHD. These people are often described as stupid, lazy, disorganised, wild, out of control or woozy on drugs. But the reality is altogether more complex, and deeply moving.