The primary duty of the SPS is the custody of inmates in conditions of appropriate security and control. It also provides a range of opportunities for inmates to exercise personal responsibility and prepare for release. A statement of aims, objectives, operating principles, and values is followed by an outline of key performance measures and targets. Performance measures are the number of inmates unlawfully at large, the number of significant incidents, the number of serious assaults on staff and inmates, basic quality of life for inmates, the amount of available opportunities for inmates' self-development, time out of cell for unconvicted inmates, average annual cost per inmate, and the amount of staff sick leave. A strategic overview includes a statement of strategic priorities; they include setting and achieving standards, a change in management style that transfers decisionmaking and financial responsibility to governors-in-charge, the delivery of appropriate human-resource skills, and the implementation of the estates strategy. The latter seeks to balance the delivery of the "opportunity agenda" with accommodation requirements. Other report sections address planning assumptions, the human resources strategy, the estates strategy, the information systems strategy, key objectives for prisons and directorates, and financial projections. Appended summary of key targets, plans for individual establishments, key objectives for individual facilities, and data on the inmate population and staff