Abstract This study examined the linkages among girls’ best friendships and romantic relationships and accounted for the level of dating involvement as a moderating variable. Social exchange and Sullivan's socioemotional theories served as guides in this process. Questionnaires were administered to 446 girls aged 15–19 years. Results showed that: (a) dating is associated with more positive and less negative interactions with best friends; (b) increasing age and dating involvement are linked with increased reliance on romantic partners; (c) romantic relationships have more negative interactions than best friendships; and (d) peer-network size and structure is related to dating behaviour. Mid to late adolescence is a time when girls shift attention away from friends and towards romantic partners.