The development of the use of polymeric materials in the form of geosynthetics has brought about major changes in the civil engineering industry. Geosynthetics are available in a wide range of compositions appropriate to different applications and environments. Over the past three to four decades, civil engineers have grown increasingly interested in geosynthetics and in understanding their correct use. Simultaneously, significant advances have been made in the use of geosynthetics in civil engineering applications as well as in the areas of aquaculture, agriculture and mining engineering. These developments have occurred because of the ongoing dialogue among leading engineers and researchers from several organizations and academic institutions. This concise introductory textbook on geosynthetics deals with the basic concepts of the subject, especially for meeting the requirements of senior undergraduate/graduate students as well as of practising engineers who have not been exposed to geosynthetics thus far. It includes recently developed fundamental concepts and new applications covering the use of polymer and other fibres in soil improvement.