Demand for quantitative research skills is at an all-time high, while at the same time academic careers are becoming less and less safe and attractive. If you are a PhD student or post-doc, should you be thinking about making the dreaded jump to industry? What are the opportunities and trade-offs? What kind of preparation do you need to transition? Can you ever go back to academia, or even maintain ‘dual citizenship’? And just what do data scientists do for companies?