PURPOSE: To understand the preferences and attitudes of patients and family caregivers on disclosure of cancer diagnosis and prognosis in an Indian setting. METHODS: Overall, 250 adult patients with cancer and 250 family caregivers attending the outpatients of a tertiary cancer hospital for the first time were recruited purposively. The mean ages of patients and caregivers were 49.9 years (range, 23-80 years) and 37.9 years (range, 19-67 years), respectively. Separately, they completed prevalidated, close-ended preference questions and were interviewed for open-ended attitude questions. RESULTS: A total of 250 adult patients (response rate, 47.17% overall, 73.2% in men, and 26.8% in women) and 250 family caregivers (response rate, 40.65% overall, 84.0% in men, and 16.0% in women) participated. Significant differences were observed in the preference to full disclosure of the name of illness between patients (81.2%) and caregivers (34.0%) and with the expected length of survival between patients (72.8%) and caregivers (8.8%; P <.001). The patients felt that knowing a diagnosis and prognosis may help them be prepared, plan additional treatment, anticipate complications, and plan for future and family. The caregivers felt that patients knowing a diagnosis and prognosis may negatively affect the future course of illness and cause patients to experience stress, depression, loss of hope, and confidence. CONCLUSION: Patients with cancer preferred full disclosure of their diagnoses and prognoses, whereas the family caregivers preferred nondisclosure of the same to their patients. This novel information obtained through a large study with varied participants from different parts of the country will help formulate communication strategies for cancer care.