This volume provides broad insights to the most recent discoveries in telomere biology, with current applications in tumor diagnostics and future potentials in therapy. Special features of diverse organisms are presented, with ciliates, the "telomerase discoverer organisms"; yeasts, the "molecular genetisists' toy for eukaryotes"; including plants and insects as well. 28 chapters were written by a group of leading research scientists, working in the telomere/telomerase fields today. This book will be a core reference for any physician, scientist or "educated reader" with an interest in the exciting developments in this research field.