"Karuna is a Sanskrit word and is used in Hinduism and Buddhism. It is translated to mean any action that is taken to diminish the suffering of others and could also be translated as "compassionate action." - From the ICRT Institute.
Karuna Reiki ® was founded by William Lee Rand of the International Center for Reiki Training (ICRT). Over the course of his long Reiki practice, Master Rand encountered many other practitioners from different branches of teachings. From them, he had learned and collected various symbols of power and techniques that are used to heal. In 1995, he gathered his most trusted students to experiment with these symbols and to incorporate them into a Reiki practice. This practice became known as Karuna Reiki ®. Some of these symbols may be recognized from other types of traditions, however, in Karuna Reiki ® they are used for healing and compassion.
What William Lee Rand and his students found was that Karuna Reiki ® seems to be a more potent form of Ki energy. In Usui Reiki, the Ki addresses imbalances in a person’s energy field, whereas Karuna Reiki ® addresses damage to a person’s energy field. Either caused by physical, emotional, or spiritual trauma. Karuna Reiki ® also has the ability to work at the karmic level, dealing with any past life issues that may be affecting you today. For this reason, only Master level Usui Reiki practitioners may be trained in Karuna Reiki ®.
It should also be understood that Karuna Reiki ® should not be considered a replacement of Usui Reiki. It is a further study of what Reiki energy is and how best to use it for greater healing. One should either have a healing session or take a class to form their own opinions of Karuna Reiki ®. Everyone has different reactions to energies. Just because it is thought to be a deeper study, doesn’t mean it is more or less powerful to a person using the energy for healing. It is entirely dependent on the healer’s intuition and perspective.