Modern culture has become a study in sleep deprivation. When we deprive ourselves of sleep, we deprive ourselves of its restorative powers. One of the first casualties is motivation. Loss of sleep soon saps our ability to experience pleasure. It cuts down our productivity and puts our bodies in harm's way: 33% of traffic accidents are traceable to daytime sleepiness. In the final medical tally, sleep has emerged as the single most important determinant in longevity - more critical than any other risk factor, including smoking, heart disease or heredity.The Promise of Sleep is a wake-up call to us all about the dangers of abusing our delicate biological clocks and to start taking sleep seriously as the foundation of good health.