A comparison between the influences of four subjective ages' variables (cognitive age, ideal age, youth age and discrepancy age) on the senior travellers' behaviours reveals that the discrepancy between the cognitive age and the ideal age is the most influential variable. Particularly, this discrepancy age plays a significant role on senior travel motivations and perceived risks: the larger the discrepancy is, the more seniors would worry about the travel risks and would look for relaxation while on holidays. Besides, the discrepancy age is able to discriminate between the four travel motivations segments identified with a survey conducted on 300 French senior travellers: relaxed intellectual; knowledge hunters; hesitating, non intellectual and non sportive and finally active and open minded senior travellers. This segmentation could help marketers in developing new tourism products for the senior market.