The study was designed to explore qualitatively developmental differences in disagreement negotiation and resolution skills between adolescent and young adult romantic partners. Twenty adolescent and 20 young adult couples participated in the study. The Knox inventory was used to measure the level of disagreement between partners on ten domains (e.g., friends or money). Partners were asked to discuss and resolve their greatest disagreement. Joint discussions were recorded and transcribed. A qualitative analysis of interactions revealed major differences between the two age groups, in discussion management and in strategies for resolution. Adolescents' interactions were concrete, concise, and brief. Their resolution of disagreements was based on superficial agreements or coercion of one partner. Young adults' interactions were more rich and developed, disagreements were understood as metaphors for the relationship, and resolution was accomplished by the two partners as a result of discussion. These differences are discussed in light of the theories on the development of romantic relationships.