This study explores heterogeneity in employment trajectories occurring before, during, and after the transition to lone parenthood (LP) in a life-course perspective. Lone mothers are usually both primary caregivers and breadwinners: The transition into LP leads to an increase in economic and care needs that may compromise work-family balance and condition labor-market participation. Our mixed-method approach combines biographical calendars (SHP data, N=462) and semistructured interviews (N=38) of lone mothers residing in Switzerland. Using sequence and cluster analysis, we reconstruct employment trajectories around the transition to LP and estimate the probability of specific patterns by individual and household characteristics that help or hinder labor-market participation. We then contrast these results with findings from a content analysis of narrative interviews focusing on values and norms concerning work and care. We identify five employment patterns characterized by either an increase in labor supply (especially for those with more/older children) or by stability in or out of the labor market (for highly educated or younger mothers respectively). The analyses of the narratives provide insights on how employment opportunities and decisions differ by entry mode into LP, the postseparation relationship with the children’s father, and the ability to mobilize individual, social and institutional resources. Our findings suggest that effective policies encouraging lone mothers’ labor-market participation should consider their normative priorities when facing work and care trade-offs and the availability of informal and formal support, which ultimately shapes their work-related decisions.