Social engineering—I can remember when searching for that term led you to videos on getting free burgers or dates with girls. Now it seems like it's almost a household term. Just the other day I heard a friend of the family, who's not in this industry at all, talking about an email scam. She said, “Well, that's just a great example of social engineering!” It threw me for a loop for a second, but here we are, eight years after my decision to start a company solely focused on social engineering, and now it's a full-blown industry and household term. If you were to just start reading this book it would be easy to mistake my intentions. You might think I am fully okay with arming the bad guys or preparing them for nefarious acts. That cannot be further from the truth. When I wrote my first book, there were many folks who, during interviews, got very upset with me and said I was arming the malicious social engineers. I felt the same then as I do now: you cannot really defend against social engineering until you know all sides of its use. Social engineering is a tool like a hammer, shovel, knife, or even a gun. Each has a purpose that can be used to build, save, feed, or survive; each tool also can be used to maim, kill, destroy, and ruin. For you to understand how to use social engineering to build, feed, survive, or save, you need to understand both uses. This is especially true if your goal is to defend. Defending yourself and others from malicious uses of social engineering requires that you step over into the dark side of it to get a clear picture of how it is used. I was recently chatting with AJ Cook about her work on Criminal Minds, and she mentioned that she often has to meet with real federal agents who work serial-killer cases to prepare herself for playing the role of JJ on the show. The same idea applies directly to this book. As you read this book, do it with an open mind. I tried my hardest to put the knowledge, experience, and practical wisdom I have learned over the last decade onto these pages. There will always be some mistakes or something you don't like or something you might feel was not 100% clear. Let's discuss it; reach out to me and let's talk. You can find me on Twitter: @humanhacker. Or you can email me from one of the websites: www.social-engineer.org or www.social- engineer.com. When I teach my five-day courses, I always ask the students to not treat me like some infallible instructor. If they have knowledge, thoughts, or even feelings that contradict something I say, I want to discuss it with them. I love learning and expanding my understanding on these topics. I extend the same request to you. Finally, I want to thank you. Thank you for spending some of your valuable time with me in the pages of this book. Thank you for helping me improve over the years. Thank you for all your feedback, ideas, critiques, and advice. I truly hope you enjoy this book. —Christopher Hadnagy