Daily time-budget activity reports on more than 30,000 individuals in urban-industrial sites in 11 countries have been published. This is an analysis of the data on sleep patterns. The amount of sleep on weekdays by men and women did not differ. On days off the amount of sleep increased by about 90 minutes with the females obtaining significantly less sleep. About 2% of the employed men and women slept less than 5 hours and about 5% slept more than 10 hours on week days. There were significant country and site effects. These data indicate a common sleep demand averaging about 8 hours. This demand, however, shows wide individual differences and is responsive to site and employment conditions.