This handbook is about translating insights from experts in code and data into practical terms for empirical social scientists. We are not ourselves software engineers, database managers, or computer scientists, and we don’t presume to contribute anything to those disciplines. If this handbook accomplishes something, we hope it will be to help other social scientists realize that there are better ways to work. Much of the time, when you are solving problems with code and data, you are solving problems that have been solved before, better, and on a larger scale. Recognizing that will let you spend less time wrestling with your RA’s messy code, and more time on the research problems that got you interested in the first place.