Once opened and populated, warming centers typically offer only the most bare-bones of service: a cot and perhaps a bowl of hot soup. They are generally operated with one or more experienced professional staff person. This is due to the difficulties which untrained volunteers might encounter in dealing with the clientele. Often, users of warming centers are persons who are not participating in routine homeless shelter services due. This may be due to disciplinary problems and issues with behavior, such as drinking and fighting. Sometimes it takes a professional to figure out who might be disruptive or even dangers as opposed to who is just a little bit eccentric or odd. That is why it is important to have experienced staff.