SOME OF THE groups called cults, especially those that are noncommunal, coexist easily with the outside world. Although members may have unorthodox beliefs, their appearance and manner do not make them stand apart from the rest of society. Their meetings and activities do not involve outsiders or impinge upon them, and efforts to recruit are low-key.

Occasionally a particular belief or practice will cause a conflict with mainstream attitudes. For example, Christian Scientists sometimes clash with authorities over the issue of medical care, usually for a child who is being kept from some traditional medical treatment because of the parent's beliefs. However, the issue usually remains limited to the specific incident and does not draw the entire group into tension with the outside world.

Some cults reach out to the community around them in an effort to become...