We systematize the knowledge on data breaches into concise step-by-step breach workflows and use them to describe the breach methods. We present the most plausible workflows for 10 famous data breaches. We use information from a variety of sources to develop our breach workflows, however, we emphasize that for many data breaches, information about crucial steps was absent. We researched such steps to develop complete breach workflows; as such, our workflows provide descriptions of data breaches that were previously unavailable. For generalizability, we present a general workflow of 50 data breaches from 2015. Based on our data breach analysis, we develop requirements that organizations need to meet to thwart data breaches. We describe what requirements are met by existing security technologies and propose future research directions to thwart data breaches.