This study focuses on helping family caregivers of people with advanced cancer to make better healthcare decisions together. Advanced cancer means the cancer is very serious and has spread or come back. The study uses a special method called the Multiphase Optimization Strategy (MOST) to test different ways to train caregivers. Caregivers will learn skills like decision partnering, communication, and using an Ottawa Decision Guide to support patients. The goal is to see which training methods work best to reduce stress and improve decision-making for both caregivers and patients. The study will last for 24 weeks and involve up to 256 caregivers. Participants will be randomized, which means they are assigned by chance to different training groups.

• This study lasts about 24 weeks and involves monthly follow-up calls.
• You will participate in different training sessions to support decision-making.
• Caregivers must be 21 or older and help a person with advanced cancer.