This introduction sets the background to the Handbook of Financial Markets; a volume of 22 chapters on the state of different financial markets. It gives a discussion of the historical background to financial markets and the linkages between finance and the broader economy, emphasizing the importance of central banks in modern finance. It explains how the chapters are linked together and are not just a collection of standalone essays. The introduction gives a roadmap of the sections of the book, on central banking, financial intermediaries, money markets, capital markets, and derivative markets; and describes how the book addresses both historical background and recent market developments, as well as highlighting open questions.