Mutual support groups that schedule virtual "meetings" via the Internet. Included are e-mail listserv groups (which distribute posted messages to participants via e-mail), bulletin/message boards (whose postings are restricted to people who register), newsgroups (whose postings are unrestricted and open) and chat groups (which permit real time discussion) that are devoted to providing support for participants around a particular issue. Internet support groups are generally available around the clock; and are convenient for people with limited mobility, serious health issues or transportation problems, who don't have time for face-to-face meetings, or who simply wish to maintain their privacy and remain anonymous. They may be the only option for individuals with rare disorders or other unusual problems who are unlikely to find enough people in their local area to form a support group. Internet support groups may be monitored by professionals, but most are not.

Mutual support groups whose members are people who have experienced a loss such as the death of a loved one, divorce or separation and are trying to cope with their grief as a result. The groups meet in-person, by telephone or via the Internet; and focus on helping participants accept their loss, express their grief, move through the bereavement process and put their lives back together.

Mutual support groups whose members are family, friends, significant others, non-familial caregivers or attendants who are caring for someone who has a temporary, chronic, life-threatening or terminal illness or disability or who is elderly and increasingly unable to provide for his or her own care. The groups meet in-person, by telephone or via the Internet; and provide emotional support, information and resources to help participants ensure their own well-being while remaining involved in the intense care of a loved one. Also included are care receiver support groups that help people who have a caregiver cope with the fact that they require care. Care receiver support groups are often offered in conjunction with caregiver support groups and are structured to allow care receivers to participate in their own group while their caregiver attends another.

Mutual support groups whose members are people who have specific disabilities, illnesses or other health conditions, their families and friends. The groups meet in-person, by telephone or via the Internet; and provide an opportunity for participants to share information, resources, practical tips for daily living and encouragement about issues related to the disability or health problem.

Any of a broad group of malignant neoplasms which are either carcinomas which have their origin in epithelial tissues or sarcomas which develop from connective tissues and those structures which had their origin in mesodermal tissues (the muscular, skeletal, circulatory, lymphatic and urogenital systems and the linings of body cavities). Cancer is invasive and tends to metastasize to new sites spreading directly into surrounding tissues or through the lymphatic or circulatory systems.

Individuals who have experienced a loss, such as the death of a loved one or pet, divorce or separation, estrangement from a family member or any other kind of significant loss whose own patterns of personal, social and familial coping have been significantly affected as a result.

The parents, children, spouses, partners, friends or other relatives or significant others of people who have cancer, whose own patterns of personal, social and familial coping have been significantly affected by concern about the individual.