Out-of-hospital cardiac arrest (OHCA) is a lethal health problem that affects between 236,000 and 325,000 people in the United States each year. As resuscitation attempts are unsuccessful in 70-98% of OHCA cases, Emergency Medical Services (EMS) personnel often face the needs of bereaved family members. Decisions to continue or terminate resuscitation at OHCA are influenced by factors other than patient clinical characteristics, such as EMS personnel's knowledge, attitudes, and beliefs regarding family emotional preparedness. However, there is little research exploring how EMS personnel care for bereaved family members, or how they are affected by family dynamics and the emotional contexts. The aim of this study is to analyze EMS personnel's experiences of caring for families when patients suffer cardiac arrest and sudden death. The study is based on a hermeneutic lifeworld approach. Qualitative interviews were conducted with 10 EMS personnel from an EMS agency in southern Sweden. The EMS personnel interviewed felt responsible for both patient care and family care, and sometimes failed to prioritize these responsibilities as a result of their own perceptions, feelings and reactions. Moving from patient care to family care implied a movement from well-structured guidance to a situational response, where the personnel were forced to balance between interpretive reasoning and a more direct emotional response, at their own discretion. With such affective responses in decision-making, the personnel risked erroneous conclusions and care relationships with elements of dishonesty, misguided benevolence and false hopes. The ability to recognize and respond to people's existential questions and needs was essential. It was dependent on the EMS personnel's balance between closeness and distance, and on their courage in facing the emotional expressions of the families, as well as the personnel's own vulnerability. The presence of family members placed great demands on mobility (moving from patient care to family care) in the decision-making process, invoking a need for ethical competence. Ethical caring competence is needed in the care of bereaved family members to avoid additional suffering. Opportunities to reflect on these situations within a framework of care ethics, continuous moral education, and clinical ethics training are needed. Support in dealing with personal discomfort and clear guidelines on family support could benefit EMS personnel.