Objectives: Capture change in family members' experiences as they look after patients during chemotherapy, and understand variability in their needs for support. Methods: Longitudinal digitally-recorded qualitative semi-structured interviews with family carers at the beginning, mid-point, and end of treatment. Twenty-five family members (17 women, 8 men), mean age 53, were interviewed. Fifteen participants were supporting a relative having chemotherapy with curative intent, and 10 a patient receiving palliative chemotherapy.