Guided by attachment theory, a 2-part study was conducted to test how perceptions of relationship-based conflict and support are associated with relationship satisfaction/closeness and future quality. Dating partners completed diaries for 14 days (Part 1) and then were videotaped while discussing a major problem that occurred during the diary study (Part 2). Part 1 reveals that more anxiously attached individuals perceived more conflict with their dating partners and reported a tendency for conflicts to escalate in severity. Perceptions of daily relationship-based conflicts negatively impacted the perceived satisfaction/closeness and relationship futures of highly anxious individuals, whereas perceptions of greater daily support had positive effects. Pan 2 reveals that highly anxious individuals appeared more distressed and escalated the severity of conflicts (rated by observers) and reported feeling more distressed. The authors discuss the unique features of attachment anxiety and how changing perceptions of relationship satisfaction/closeness and stability could erode commitment over time.