After hundreds of performance investigations, some patterns begin to emerge. You could save a lot of time here, or find the root cause more easily there. In this talk, you'll see what I learned from years of performance work in the field, which processes and tools work, and what I think can still be improved. First, we'll talk about anti-methods for performance investigations and the USE checklist. Then, we'll talk about ideal performance investigation tools and which tools can satisfy these needs today. We'll conclude with some mistakes you can make when working with statistics and reports. I'll take you on a tour of a couple of my most challenging performance investigations.