In this paper, I consider what difference knowledge of outcomes – both past and future – might make to the rationality of praying for them on a traditional theistic model. More specifically, I address four questions: (1)‘Could it be rational to pray for outcomes one knows will obtain?’; (2)‘Could it be rational to pray for outcomes one knows will not obtain?’; (3)‘Could it be rational to pray for outcomes one knows have obtained?’; (4)‘Could it be rational to pray for outcomes one knows have not obtained?’. I argue that, on certain common theistic assumptions, the answer to all of these questions is yes.