The officiants of a special ritual, cult may be selected in a special way. It may be hereditary, or an individual may be dedicated to it at child-birth, training may also be required.

In some societies an 'expert' may be powerless but he can become the vehicle of certain spirits - and there may be 'possession'. In this state he performs actions associated with the spirit or spirits that will be recognized as such by onlookers - he may pronounce prophecies, give direction to offer sacrifices, etc.

There may be experts associated with special activities such as hunting, gardening, warfare, etc. These would be responsible for the ritual deemed necessary for success in that activity.

These experts may be referred to as: rainmakers, priests, shaman, medicine men, secret chiefs, etc.

Eskimos

They have intermediaries between them and the spirits. At times fo great tragedies the intermediary will hold a seance with the spirit world to try and discover the cause.

Aziana

The Aziana have a leading priest who mediates for them in the large ceremony to cleanse the land from evil spirits that cause misfortune on their gardens, animals and themselves.

Yuroks

A priest and a girl helper prepared the ground for the World Renewal Dance. He made a speech exhorting them to do the right things. They did various other ceremonies necessary for the purification of the world.

Dusun

Ritual experts are used to divine the nature of the aillness, to undo the unfortunate events, to restore matters to original conditions, to prevent sickness or provide protection against impending harm. The female experts are supposed to be best able to deal with affects of birth, illness, death, luck, etc. The male experts are able to deal directly with the creator to elicit intercession in epidemics, floods, drought, war and crop failures.