The book is actually organized by seven questions that up stream leaders need to answer, and i won't belabor those right now. But the point is there's a lot of things we have to think about kind of simultaneously as we move up stream, and we've hit on several of them. And i think the word that i would i use to describe what ju da said is precision intervention. You're trying to find that thing that leave of that particular part that will have a disproportion effect in in changing the dynamic.