Children’s behavior and personality are equally conditioned by genes and environment. But, which environment? Studies on siblings, twins and adopted children say that the environment outside home counts a lot more than the home environment. Similarities between parents and biological children are prevalently due to shared genes. Children are programed to succeed in a social context which is where they will spend most of their life, rather than in a domestic one. Immigrants with a strong foreign accent whose children grow up with Italian children end up speaking in Italian with no particular accent and not with one that is half way between that of their parents and that of their Italian school mates. Children are not very conditioned by the domestic environment they live in also because almost everything they see their parents do such as drive a car, smoke, drink beer, give orders, go to bed when they want or light matches is forbidden for them. In their case socializing means not behaving like their parents. Behaviors children learn are specific for the environment where they were learned. A newborn who discovers that every time he cries his mother will pick him up to feed him does not believe that crying will have this effect on his father, sister or mates at kindergarten. Kids who fight with brothers and sisters at home don’t necessarily fight at school. A Dennis the Menace at home may be very good at school or vice versa. Campaigns to stop youngsters from smoking or taking drugs or to study foreign languages will flop if aimed at single children or their families instead of children and youngsters as a group.