Every marketing manager is always looking for the most relevant and operational criteria for building a target market. It is quite clear that age is one, if not the key, criterion that drives consumer behavior. Above all, it has the advantage of being simple , real and easy to use in terms of media planning. Simplicity is abasic virtue in marketing! When age is used as the central criterion for segmentation one realizes that it is in fact statistically the best way to design a reasonably accurate model of the targeted consumer. It will therefore be relative easy for the marketing manager to think about the economic situation, financial resources, resource, main needs as to equipment and services, preferred shops, the best time to advertise, and so on.