Most innovation builds closely on existing knowledge and technology, delivering incremental advances on existing ideas, products, and processes. Sometimes, however, inventors make discoveries that seem very distant from what is known and well understood. How do individuals and firms explore such uncharted technological terrain? This paper extends research on knowledge networks and innovation to propose three main processes of knowledge creation that are more likely to result in discoveries that are distant from existing inventions: long search paths, scientific reasoning, and distant recombination. We explore these processes with a combination of a large and unique data set on outlier patents filed at the U.S. Patent and Trademark Office and interviews with inventors of outlier patents. Our exploratory analysis suggests that there are significant differences in the inventor teams, assignees, and search processes that result in outlier patents. These results have important implications for managers who wish to encourage a more exploratory search for breakthrough innovation.