Political life in Renaissance Italy was held together by political principles which underlay, or were used to justify, political proposals and decisions in practice. This wide-ranging comparative survey examines these political principles, as expressed in sources such as council debates, preambles to legislation and official correspondence, in the mid-fifteenth to the mid-sixteenth century Italy. Focusing especially on the five republics - Florence, Venice, Genoa, Siena and Lucca - the book also considers princes and signori, and the principles underlying relations between states, particularly relations between major and minor powers. Many of the ideas articulated by those confronting practical political problems ranged beyond the questions dealt with in formal treatises of political thought and philosophy. Drawing on extensive archival research, Christine Shaw explores the relationship between 'reason and experience' in the conduct of political affairs in Renaissance Italy, and the gap between theory and practice.