Theory is something that is often not highly valued by youth workers and others who work with young people. "I'm not a great one for theory. I prefer to get on with doing the job," is a not uncommon opinion. Such a view is based on a misunderstanding of the nature of theory and of the relationship between theory and practice. Specifically, it reflects the misguided notion that theory is necessarily both abstract and abstruce, something "academic" and impractical. But in fact, as Kurt Lewin once wrote, "there is nothing as practical as a good theory" (Lewin, 1952:346). Theory is essentially concerned with explanation and understanding of why things are the way they are; of why things work the way they do. It is therefore utterly indispensable to good practice, whether the practice in question is car mechanics, brain surgery or youth work.