Context:Thousands of family members worldwide are annually involved in assisted dying. Family participation in assisted dying has rarely been investigated and families' needs typically are not considered in assisted dying legislation and clinical guidelines. Objectives: To explore family caregivers' reflections on experiences of assisted suicide in Switzerland. Methods: A cross-sectional qualitative interview study conducted in the Italian- and French-speaking regions of Switzerland. Interpretation and analysis were performed using qualitative content analysis. Results: Twenty-eight close relatives and family carers of 18 patients who died by assisted suicide in Switzerland were interviewed. Family members perceived their involvement in assisted suicide as characterized by five phases; 1) contemplation, 2) gaining acceptance, 3) gaining permission, 4) organization, and 5) aftermath. Families can participate in these phases at diverse levels and with varying degrees of involvement. Important triggers for families and patients for transition between phases include patients' experiences of their life-threatening illnesses and related treatments, their increasing awareness of approaching death, and family member recognition of their loved one's unbearable suffering. Participating in assisted suicide created further demanding tasks for families in addition to their role of caregivers. Conclusion: Families appeared to be involved in the preparation of assisted suicide along with patients, irrespective of their personal values regarding assisted dying. Support for family members is essential if they are involved in tasks preparatory to assisted suicide. Clinical guidelines and policies concerning assisted dying should acknowledge and address family needs.