what is oppositional defiant disorder?

What is Oppositional Defiant Disorder or ODD? I have come across a number of children who are not only ODD, but also ADHD and dyslexic. Quite a handful to handle is an understatement. Parents are often overwhelmed by what they have to deal with and can upset the family dynamics significantly. There are some useful approaches recommended in this article. Hope you find it helpful.