We studied the psychological importance of best friend and intimate partner in the personal network of adolescents and early adults, and links between relationships and emotional problems as well as links between relationships themselves. A series of hypotheses derived from the “intimate partner (IP) general saliency perspective” and “the intimate partner (IP) early adult saliency perspective” was tested. The IP general saliency perspective predicts that the relationship with intimate partner is psychologically more meaningful than the relationship with best friend in adolescence and early adulthood. The IP early adult saliency perspective predicts that the relationship with intimate partner does not have superior psychological value in adolescence and acquires it in early adulthood. Data of Waves 1 and 3 of a six-year longitudinal study of 1041 adolescents and early adults, aged 12—23 at Wave 1, were used. Results showed that when early adults and adolescents make the shift from best friend to intimate partner, relational commitment becomes stronger and emotional problems become smaller, supporting the IP general saliency perspective. Results also showed that only in early adulthood was a stronger commitment to intimate partner related to less emotional problems, and more parental support was linked to stronger relational commitment to intimate partner. These findings clearly support the IP early adult saliency perspective. In sum, when adolescents and early adults make the transition to the intimate partnership they enter a psychologically more meaningful relationship. When individuals enter early adulthood the psychological value of the intimate partner relationship becomes more salient: the quality of the intimate relationship becomes more stable and linked to emotional adjustment.