Mediumship is the pseudoscientific practice of mediating communication between familiar spirits or spirits of the dead and living human beings. Practitioners are known as "mediums" or "spirit mediums". There are different types of mediumship or spirit channelling, including séance tables, trance, and ouija. The practice is associated with spiritualism and spiritism. A similar New Age practice is known as channeling.

Pseudoscience consists of statements, beliefs, or practices that claim to be both scientific and factual but are incompatible with the scientific method. Pseudoscience is often characterized by contradictory, exaggerated or unfalsifiable claims; reliance on confirmation bias rather than rigorous attempts at refutation; lack of openness to evaluation by other experts; absence of systematic practices when developing hypotheses; and continued adherence long after the pseudoscientific hypotheses have been experimentally discredited. It is not the same as junk science.