Understanding serendipity from a trajectory perspective is crucial because serendipitous findings bend the arc of progress, leading us down unexpected paths - in the process changing the direction and rate of research pursuits. Many imagine the classic "Eureka!" moments being a demonstration of such serendipity in real life, although this might be overly simplistic. There are many processes that occur before and after making an unexpected observation that, in hindsight, set the stage for these observations to become discoveries of use. Chapter 18 explores how the serendipitous discoveries of Helicobacter pylori and many modern psychotherapeutic drugs came to be, and discusses how we can more systematically cultivate conditions that allow serendipitous findings to occur.