This book addresses both domestic and foreign readers, and for that reason appears in English. Following the survey of history of the Lisbon Exchange published in 1996 by David Justino, the present text extends that medieval period to the Nineteenth century analysis to the present day. Many other Stock Exchanges in Europe and elsewhere have been studied and published by many authors, but no comparable book for Portugal has existed until the present work. The text is accessible to medium-knowledge readers. In a world of internationalization of corporations and financial institutions it is paramount that they be able to mobilize the capacities of the Capital Market to finance the economy, and to possess a thorough understanding of the role of a Stock Exchange for the efficient working of that market. Portugal is a case of great interest to developing countries, as it was able to re-instate the market after 1974, and with such success that the country joined the European Union in 1986 and the innovative Euronext Group of Stock Exchanges in 2002. The book discloses for the first time a database used to calculate a share index that was developed over three years with the help of the FCT grant PTDC/HISHIS/100132/2008, and using a methodology that makes that index comparable to common international indices and compatible with the General Index computed daily by the Exchange.