Changes in sexuality and intimacy after cancer were examined using open-ended questionnaire responses with 156 informal carers who were partners of a person with cancer. Interviews were conducted with 20 participants to examine changes in depth. Seventy-six percent of partners of a person with "nonreproductive" cancer types and 84% of partners caring for a person with cancer involving "reproductive" sites reported an impact on their sexual relationship. Cessation or decreased frequency of sex and intimacy was reported by 59% of the women and 79% of the men. Renegotiation of sexuality and intimacy after cancer was reported by only 19% of the women and 14% of the men. Reasons for changes to sexuality after cancer were the impact of cancer treatments, exhaustion due to caring, and repositioning of the person with cancer as a patient, not a sexual partner. Changes to sexuality were associated with reports of self-blame, rejection, sadness, anger, and lack of sexual fulfillment. Positive consequences of changes included accepting the changed sexual relationship and having increased closeness and intimacy. These findings reinforce the need to acknowledge the sexual needs of partners as well as people with cancer, by healthcare professionals working in cancer and palliative care.