In many parts of the world, judges are reassigned or transferred frequently. We argue that transfers undermine court productivity and cause judges to prioritize easier and recently filed cases. We test these propositions using big data from the courts of first instance in India, in which there are more than 40 million cases pending, and a research design that leverages transfers due to judge retirements at precisely age 60. The data suggest that judge transfers are frequent, occurring once every 10 months. Transfers reduce court productivity, both because transfers create court vacancies, and since portions of cases that experience judge transfers are reheard. Judges who experience transfers focus on easier and newer cases. Transfers are a major, unappreciated cause of judicial delays, particularly of difficult cases. We demonstrate how seemingly mundane judge staffing decisions shape judicial decision-making.