Nanny Shares - How do they work?

[bluebear]

I'm probably being a bit thick but... is it one nanny looking after 2 families' children in one house?
Another really stupid question... I've been perusing the nanny job sites and some of them say 'prefer sole charge' what does this mean?
Blue'Thicko'Bear

Sole charge means the mum isn't around (eg working from home). Nanny share can mean any combination of looking after the offspring of two families. My nanny share was nanny looked after two boys for two days at the 'other' home, my son for one day in my home and the other child for one day in their home (ie four days work). Often it means looking after one child for two days and another for three days in their respective home, thus making up a full time job for one person, or it can mean looking after two children for five days, with the nanny looking after them in one home for one week, the other the next and so forth. A nanny gets paid more per day for looking after two children than she does for one.

Thanks aloha - esp for the definition of sole charge...I'm back to the nanny adds now.