Publisher Summary Mobile telephony has become a part of adolescents' everyday life. The mobile telephone is used for the functional coordination of family and peer interaction; it is used by parents to allay their fear that their child is in trouble and out of reach; and it is used to tie the peer group together. Adolescents use mobile telephone to ensure that they are accessible and in demand. Within economic constraints, it allows expressive integration and enables them to participate in “gifting,” as seen in the sending and receiving of telephone calls and text messages. The mobile telephone has impact on the breadth and depth of a teen's social network, and it allows for the quantification of popularity as seen in the number of names recorded in the device and the number of messages and calls received. Finally, ownership of the “correct” type of mobile telephone shows that teens are aware of the current fashion and that they are active in the creation and maintenance of their own identity. The symbolic value of the mobile telephone often precedes its actual possession. While there is a growing “functional” need for the mobile telephone as adolescents move into the midteen years, it is also seen as an object of desire by those who are still preadolescents.