The purpose of this paper is to explore the relationships between aspects of time norms, planning of everyday activities, use of a mobile phone, and the car in families with children. The analysis is based on results from a survey with a random sample of 2000 respondents from families with children in Norway, 2005. The analysis shows that the mobile phone is very important in everyday communication among family members. Short planning time and use of the mobile phone go together. The general level of car use varies with planning horizon and the choice of the medium used for arranging and rearranging appointments. There is a relation between high frequency of car use, a short planning horizon and use of the mobile phone.