Healing is one of the three disciplines in the Black Magician trilogy, specifically known only by Guild Magicians in the Allied Lands.
Healing is said to be the most complex of the three disciplines as it takes a comprehensive knowledge of biology so as to use healing magic in an effective manner. All novices are given a basic understanding of biology and healing magic. Indeed all Kyralian magicians know enough that they can heal most of their own ailments e.g. sores, illnesses and muscular pain, and be trusted to help and heal. Healing is gradual, and can only take place via skin-to-skin contact and usually with the agreement of the person being healed as their natural magical protection can act as a barrier.
Healing comprises of knowledge of how to make medicines that can heal the body in a non magical way, simple uses of magic to force wounds closed or draw foreign material from the body and more complex uses of magic that speed up the natural healing mechanisms of the body. Magical healing of the body can clean wounds, prevent further damage and then rapidly cause the wound to close up and scar in a matter of seconds or minutes.
It is stated that often wounds are not fully healed by magic deliberately (just healed enough so that the persons natural biological healing processes can deal with it easily) so that the healer can save magic to be used on other patients.
Healing can also be used by Magician on themselves, this continuous healing allow Magician a much longer lifespan than those without magic and as suggested in 'The Ambassadors's Mission' used to fight off illness to the point that Lord Lorkin had to be explained to, by his mother Sonea, that the feelings he had after a break up 'was the clostest that non-magicians came to knowing what it felt like for non-magician to be sick'. Continuous healing is referred continually throughout all the books.
In 'The Novice' it is revealed by Lord Dannyl that he has been using his magic to suppress with great effect, his feeling of sexual desire for men. However doing so comes at the price of him having no libido or sexual feeling at all, showing that no-one can truly control their desires, or heal what isn't broken. It is also stated in The Novice that there is a fear amongst some homosexual non magicians that healing magic will reveal them to be defective, however it is explained by Lord Dannyl that homosexuality is not a disease or anything that can be 'healed'. This is also seen in 'The Ambassadors's Mission' when Sonea trys to heal a man's addiction to a foreign, highly addictive drug called 'Rot'. While she is able to heal the withdrawal symptoms she is unable to heal his addiction.