OBJECTIVES: This study developed, and established the content validity, of a conversation aid tool (CAT) for use in clinical practice with renal cell carcinoma (RCC) patients who receive a curative nephrectomy and are at high-risk of recurrence. The CAT was pilot tested in a sample of RCC patients to establish whether the CAT increases knowledge of RCC, treatment options (such as adjuvant therapy), and care options. METHODS: A cross-sectional, mixed methods design was used involving initial, exploratory interviews with RCC patients, RCC specialists and a steering group. Further content validation interviews were conducted with RCC patients and specialists. A web-based survey was conducted with RCC patients (N = 60), to compare the CAT versus a standard of care (SOC) consultation comparator tool on patient knowledge. RESULTS: Findings from exploratory interviews were used to develop the CAT. Content validation interviews demonstrated that the CAT was well understood and relevant to RCC patients. The web-based survey demonstrated that viewing the CAT significantly improved participants knowledge of RCC, and care options, when compared to the SOC. CONCLUSION: The findings highlight that the CAT is a relevant, comprehensive and well-understood tool for use in the post-nephrectomy consultation. PRACTICE IMPLICATIONS: Use of the CAT may increase patient knowledge of RCC and care options.