Those who possess the Gifts of Healing or Mind-Healing (or both) are commonly taken into Healer's Collegium, when found, and given proper training to become a Healer. Healers come in certain levels, which determine the power of the individual based on what level they are, but this level is not one given to them as in the case of Bards (see below), but rather earned and self-determining in nature.
Healers and Mages function on the same system. As there are hedgewizards & herb witches in Mages, there are similarly hedgewizards and herb witches in Healers. These are markedly more common, but in the case of these, what is uncommon is for them to realize their limitations and exact skills, and capitalize on them, but when they do capitalize on their own abilities and accept their own limitations, hedgewizards and herb witches can be extraordinarily useful. Of those more powerful than this, however, the order is much the same, again, as for Mages:
Apprentice - Journeyman - Master - Adept
Healer-Adepts are extraordinarily rare. They are far less common than Mage-Adepts, comparatively, and the sheer scope of what they can do makes them exceptionally valuable. Mind-Healers are even rarer as Mind-Healing is a rarer Gift than normal Healing, and therefore a Mind-Healer-Adept is valued higher, still, than a Healer-Adept. However, a Mind-Healer-Adept is also of exceptionally limited scope of use, but there's nearly nothing of mental disorder and trauma that a Mind-Healer-Adept could not repair.
Mind-Healing is similar in scope and ability as Empathy. An example of this is Talia's ability to help heal during the Arrow's of the Queen. Frequently a Mind-Healer also has Empathy but the reverse is also true. They are rarely found alone.