This edited volume focuses on the interplay between sleep and circadian rhythms with health, aging and longevity. Sleep is absolutely important for human health and survival, as insufficient sleep is associated with a plethora of conditions, including the poor quality of life, onset of several diseases, and premature death. The sleep-wake cycle is an evolutionary conserved neurobiological phenomenon, and is a prominent manifestation of the biological clocks localised in the suprachiasmatic nucleus (SCN). Understanding bidirectional relationship between sleep and circadian rhythms is of utmost importance and urgency, especially in the context of modern lifestyle where sleep is often out of phase with the internal body clocks, social jetlag, artificial lights and so on. The 25 chapters by leading researchers and experts from 11 countries are arranged into seven sections: understanding sleep and clock interlink in health and longevity; sleep, aging and longevity; clock, aging and longevity; melatonin, sleep and clock; genetic regulation of sleep and clock; therapeutic interventions in sleep disorders and clock misalignment; and experimental models to study sleep and clocks in aging and longevity. This book is useful for advanced undergraduate and graduate students, and researchers, educators, and other biomedical professionals.