In this article, I outline the reasons why the choice of PhD research topic has important and persistent effects on an economist's career. Although the issues raised in this article are most acute for those wishing to pursue a career in academia, there are also implications for those working outside academia. While there are many factors that determine whether an economist has a successful career, I argue that the choice of PhD topic is an issue, which deserves more attention. Although primarily targeted at PhD students, the issues raised here resonate throughout an economist's career.