I guess I am the odd man out......I have always done slow transitions and introduced children to daycare slowly and in all my kids I have never had the "cry all day" except for the only one I didn't do that for..........but that's just my opinion, it's always worked in my favour. When I worked in licensed centre care we did the cold turkey and I would say at least 75% of them cried all day for anywhere from 1-6 weeks.