Whenever you perform point-in-time-recovery or failover in PostgreSQL, a new timeline is created. In the best case, timelines help you stay sane in complicated recovery situations and keep your database consistent. In the worst case, they will thoroughly confuse you. This talk explains timelines, how they are used by the system, and how you can stay sane with them and even take advantage of them. Version 9.3 brings some improvements to the handling of timelines, these are discussed as well.