Common folklore seems to suggest that adolescents are particularly susceptible to peer influence. However, from the literature the exact age differences in susceptibility to peer influence remain unclear. The current study's main focus was to chart the development of general susceptibility to peer pressure in a community sample of 10-18 year olds (N = 464) with the recently developed Resistance to Peer Influence Scale (RPI). The one-factor structure of the RPI was cross-validated in the present sample, and the RPI was equally reliable at all ages. As expected, general resistance to peer influence increased during adolescence. In addition, gender differences were most pronounced during mid-adolescence, when girls were more resistant to peer influence than boys. These findings are explained in terms of psychosocial maturation during adolescence. (Contains 2 figures and 1 table.)