Genetic health care includes provision of information about (a) the cause of the condition, (b) recurrence risks, and (c) options for avoiding or treating the disease. This specialized aspect of health care may be offered by appropriately trained nurses, doctors or genetic counselors, but for brevity in this article the term "genetic counselor" will be used to describe any health professional providing such care. The accepted definitions of genetic counseling emphasize the transfer of information from the counselor to the client, to facilitate the client in making informed decisions (Ad Hoc Committee on Genetic Counseling, American Society of Human Genetics, 1975; Harper, 1998). However, it is important to recognize that both clients and counselors bring to the process of genetic counseling their own knowledge, values, and beliefs (Hallowell & Richards, 1997). The information provided during the genetic counseling process may not be novel to the client, and will be received against a background of the client's previous knowledge about the condition.