Purpose The treatment decisions of melanoma patients are poorly understood. Most research on cancer patient decision-making focuses on limited components of specific treatment decisions. This study aimed to holistically characterize late-stage melanoma patients' approaches to treatment decision-making in order to advance understanding of patient influences and supports. Methods (1) Exploratory analysis of longitudinal qualitative data to identify themes that characterize patient decision-making.(2) Pattern analysis of decision-making themes using an innovative method for visualizing qualitative data: a hierarchicallyclustered heatmap. Participants were 13 advanced melanoma patients at a large academic medical center. Results Exploratory analysis revealed eight themes. Heatmap analysis indicated two broad types of patient decision-makers. BReliant outsiders^relied on providers for medical information, demonstrated low involvement in decision-making, showed a low or later-in-care interest in clinical trials, and expressed altruistic motives. BActive insiders^accessed substantial medical information and expertise in their networks, consulted with other doctors, showed early and substantial interest in trials, demonstrated high involvement in decision-making, and employed multiple decision-making strategies. Conclusion We identified and characterized two distinct approaches to decision-making among patients with late-stage melanoma. These differences spanned a wide range of factors (e.g., behaviors, resources, motivations). Enhanced understanding of patients as decision-makers and the factors that shape their decision-making may help providers to better support patient understanding, improve patient-provider communication, and support shared decision-making.