This book fills an emptiness in the Social Sciences’ sphere. Its author, the distinguished linguist Sergio Valdés Bernal, offers a historical panorama of linguistics’ development as a science and its relationship with ethnology, sociology, psychology and anthropology. It also provides a wide vision of the problems and characteristics of the study of natural languages, in a pleasant style and with updated information, for the specialists whose disciplines are related to language. In general, this is a text which gives prime importance to the language as distinctive feature that defines the human being.