Purpose <p>More people are living longer with stage IV cancer due to advances in cancer treatments. However, individuals living with advanced cancer must navigate unique day-to-day challenges and experiences that may be incompletely understood by their health care team. This study aims to better understand the activities, decisions, and experiences that characterize a “good day” versus a “bad day” for individuals living with advanced cancer.</p> Methods <p>Twenty participants with stage IV cancer completed semi-structured interviews which involved rating the quality of their day as well as characterizing their experiences and activities during the day. Participants were also asked to describe a theoretical “very good day” versus a “very bad day” for them personally, as well as advice they would give to another patient with advanced cancer about how to make a day better. Thematic analysis was used to analyze interview transcripts and identify common themes across participants.</p> Results <p>Interviews revealed that “good days” were associated with feeling like oneself before cancer, bringing oneself to engage in activities that bring wellness and joy, feeling connected to others, feeling accomplished, and practicing positive thought patterns. On the other hand, loss of control, uncertainty/unpredictability, disruptive physical symptoms, negative experiences with health care, and inability to reach one’s goals were common on “bad days.”</p> Conclusions <p>This qualitative study highlighted common themes in what defines good and bad days living with stage IV cancer. Understanding individual values and priorities may help care teams support people with advanced cancer to optimize their quality of life and functioning and navigate treatment decisions.</p>