There is a growing recognition that the carers of cancer patients require information. A key source of this information is the formal health care system that patients, and thus carers, encounter. However, the research literature suggests a lack of clarity on the part of service providers concerning the type, amount, timing and purpose of information for carers. This lack of clarity is reflected in the ways carers have been ‘tacked on’ to patients and thus are often treated as co-clients.