An alternate title for this book might have been "Lessons Learned from a Lifetime of Data Analysis." Drawing on 40 years of study, practice, instruction, and consultation, this book provides brief answers to many of the commonly occurring questions that arise when people begin to use process behavior charts. While the first chapter recaps some material from Understanding Variation, the rest complement and complete the message of that book. In every case the objective was to enable you to better and more easily use process behavior charts to get the most out of your processes and operations. Since not all sources of information about SPC are equally reliable, some of the chapters are, of necessity, focused on mistakes and misinformation that are currently in circulation. In the interest of completeness, these chapters also include enough of the background material to justify the answer given. In addition, citations are given for those who wish to delve more deeply into any particular topic.