This chapter examines the continuing significance of prerogative powers (sometimes referred to as the Royal Prerogative). Prerogative powers are those that were originally exercised by the monarch before the modern parliamentary system was established. While most prerogative powers have now been replaced by statutory powers, they remain important in some contexts, for example in relation to the deployment of armed forces abroad, the conduct of the United Kingdom’s foreign affairs, and the prorogation of Parliament. As well as considering these issues the Chapter also looks at reform of the prerogative.