In recent decades, the primary setting for oncology treatment has shifted from the hospital inpatient unit to the outpatient clinic, leaving nearly 4.6 million family caregivers responsible for most of the day-to-day, round-theclock cancer care provided in the United States. Cancer caregiving often occurs in a highly stressful emotional and social context, leaving caregivers vulnerable to significant, potentially long-lasting, adverse effects. Although palliative care teams are ideally positioned to help family caregivers cope with the numerous stressors they encounter, there is little evidence on which to base cancer caregiver support in the outpatient palliative care clinic. To address the pressing need for research on caregiver interventions in this setting, an interdisciplinary team of investigators will conduct a multisite, randomized trial of problem-solving therapy for family caregivers of individuals with cancer who are receiving outpatient palliative care. Potential barriers and facilitators to the adoption of problem-solving therapy in both rural and urban clinics will also be examined, resulting in a greater understanding of the context in which the therapy will ultimately be delivered if shown to be effective. The study’s specific aims are as follows: 1) determine the effect of problem-solving therapy on psychological distress among family caregivers of patients with cancer receiving outpatient palliative care; 2) measure the effect of problem-solving therapy on positive aspects of caregiving among family caregivers of patients with cancer receiving outpatient palliative care; and 3) identify potential barriers and facilitators to the adoption of problem-solving therapy for family caregivers in outpatient palliative oncology. At the conclusion of the study, investigators will broadly disseminate findings regarding the effectiveness of problem-solving therapy, and they will be well positioned to promote family caregiver wellbeing through the routine and sustained delivery of problem-solving therapy in outpatient palliative cancer care.