Objective: Family caregivers (FCs) of cancer patients often experience high distress. This randomized clinical trial assessed the feasibility and preliminary effects of an intervention to improve FC supportive care. Method: A pragmatic and minimal intervention to improve FC supportive care was developed and pretested with FCs, oncology team, and family physicians to assess its relevance and acceptability. Then, FCs of lung cancer patients were randomized to the intervention or the control group.