The present study examines different processes leading to lifestyle homogamy in married and cohabiting couples using data from the German Socioeconomic Panel (n = 3,490 couples). The analyses first suggest that alignment over time promotes homogamy of leisure-related lifestyles, especially with respect to action-oriented activities. However, intermediate stages in the life course (i.e., phases of active parenting and labor force participation) tend to inhibit alignment, whereas cues indicating a high-quality match (e.g., educational homogamy and being in a long-term or a marital relationship) promote alignment. Second, we find evidence for selection effects in that not only homogamy but also convergence of lifestyles over time may increase couples' resilience to relationship breakup.