The Spanish language is not restricted to Spanish-speaking countries, for its knowledge and use have long spread beyond national borders. The current internationalization process of Spanish draws on various factors, such as cultural prestige, language teaching, the intensification of supranational contacts, migratory flows and virtual and digital communication - all of which are the result of a highly interconnected society. Europe is a major player in this process, with almost 100 million people communicating in Spanish. While the social and cultural dynamics associated to the Spanish language in the United States have been extensively studied, those observed in Europe are still largely unknown. One way of describing the internationalization of Spanish is language demography - an interdisciplinary approach aimed at quantifying potential users of the Spanish language and explaining how this community has been formed. This book analyzes Spanish-speaking populations in Europe, describing their main trends and explaining their most significant dynamics, migration and education. Main aspects include migratory contacts, the intergenerational transmission of the Spanish language, the position of Spanish in European educational systems and the role of translation and communication technologies.