Royal Prayer may be a response to personal, natural or man-made disaster, an act of dedication or an expression of national celebration. From local origins thousands of years ago, it has expanded to encompass the exploration of earth and space, the development of nuclear theology and the challenges presented by quantum physics. The blessing of ships down the ages has attracted royal prayer for surprisingly practical reasons, from Nile reed boats to ocean-going ballistic missile submarines. Unexpectedly, royal prayer has also helped to improve the standing of women in society; today it recognises the presence of different faiths amongst those who serve at sea, on land and in the air. The author draw on prayers both for and of the Royal Family (and those directly associated with them in royal service) in the Archives of Her Majestys Chapel Royal and other national repositories and private collections, in this sometimes startling appraisal of the place and significance of Royal Prayer.