This is a new study and provides an examination of the American presidency centred on Ronald Reagan's tenure of office. The popular image of Ronald Reagan is one of an unintelligent, bumbling, retired B-movie act. This stereotype is challenged in this analysis, which argues that Reagan was not only one of the most popular of the post-war presidents but also one of the most effective in achieving key policy objectives in the economy and defence. It argues that under Reagan's leadership the presidency was revitalized and the fortunes of the Republican Party improved dramatically; and that there were major changes of direction in both domestic and foreign policy during his years in office. It also maintains that placed in the appropriate systemic and historical context, Reagan emerges as one of the most successful and important presidents of the 20th century.