This study examined the extent to which a one-year difference in age can influence college students' reported communicative behaviours in both the USA and South Korea. Korean students differentiated themselves far more than their American counterparts from other students one-year older or younger than themselves. The former reported that students one-year younger should show respect and be careful about their language use to others one-year older than them whilst also contending that those one-year older should show respect to those one-year younger. A compelling way of explaining such cultural differences in sensitivity to age is proposed through relativity theory in that Koreans may have a stronger tendency for seeing, thinking and acting in relativistic terms. Furthermore, the finding that Korean students contend that they have to be respectful towards others one-year younger than themselves can be better explained by relativity than recourse to any individualism-collectivism distinction. (Contains 2 tables.)