This book provides a comprehensive overview of aging and its mechanisms through the prism of telomere length and its link to lifestyle parameters and environmental pollutants, diseases where telomere length attrition is prominent, and therapeutic approaches to slow down or prevent the process of telomere length reduction. It also provides an extensive comparison of the methodology for telomere length determination and characterization. The book will help researchers in any discipline to obtain an in-depth and broad knowledge of the most recent advances in telomere research written by specialists in the field. It is also addressed to the readers interested in gaining an insight into the processes of aging and those factors that affect “graceful” aging, enabling them to extract even useful tips in improving their everyday habits.