Non-disclosure of a cancer diagnosis is a common practice in Asian cultures. However, little is known about the reasons for (non)disclosure among caregivers and the psychological experience of (non)disclosure on patients. This thesis reports four studies on cancer diagnosis (non)disclosure in India using the Common Sense Model of illness representations as a theoretical framework. Study 1 explored the experiences of, and reasons for, (non)disclosure among family caregivers of cancer patients using a qualitative methodology. Informing caregivers cited a range of reasons for informing including patient's suspicion, preparation, patient's personality, lack of control, patient's emotional well-being and self-belief. In contrast, non-informing caregivers cited patient's emotional well-being, patient's personality, jeopardizing patient's lifespan and family concerns as reasons for not informing. Study 2 examined differences between informing and non-informing caregivers on various demographic, medical and psychological variables. Reasons for, and for not, informing were the most important discriminating variables; informing caregivers more likely to agree with preparing the patient and patient's personality as reasons for informing, whereas noninforming caregivers more likely to agree with longevity and patient's personality as reasons for not informing. Study 3 explored the experiences of (non)disclosure in cancer patients using a qualitative methodology. Non-informed patients had an intense negative experience of the illness and used only passive coping strategies, whereas informed patients used a range of coping strategies. Study 4 investigated differences between informed and non-informed patients on various demographic, medical and psychological variables. Non-informed patients were less educated, were less likely to be involved in medical decision-making, were less likely to be having a combination of treatments, had weaker illness coherence, and were less likely to engage in a range of coping strategies. The thesis findings have important implications for both patient care and our understanding of the role of illness perceptions in caregivers and patients.