The people using the shelter let themselves in and out, clean up after themselves, and govern themselves. Self-managed shelters have very strict criteria, including sobriety, cleanliness, the ability to get along with others, and participation in governance and chores. It may be staffed by paid professionals assisted by volunteers, or residents of the shelter may take a large amount of responsibility while staff or volunteers or both are still in charge. Most emergency shelters are open during the night only. Most shelters accept referrals only, not people who come and knock at the door.
Couples often stay in co-ed shelters where they sleep separately.
A shelter open only on nights when the weather is dangerous to the survival of people sleeping outdoors. Also accepts anyone. Respite Beds for people who need bed rest but are not sick or injured enough to be in the hospital. Some are 24-hour shelters. Most have a time limit, because there is more need than there is shelter.