William Lee Rand, the person behind Karuna Reiki, is an American Reiki Master who lived in Hawaii before transferring to Michigan. He discovered the concept as early as 1989, but didn't officially give it a name until 1995. His new Reiki concept was soon referred to as the Karuna Reiki, which means the Reiki of Compassion.
The development of Karuna Reiki was actually an accident. William Lee Rand was a metaphysical student focusing on rebirthing and hypnosis, prior to receiving his first Usui Reiki training. He had been very interested in these subjects ever since he was 18 years old. His interest led him to become a Reiki Master in 1989. Around that time, he was given symbols that were not traditionally used in Reiki but were believed to have inherent energy.
He filed this information until he found the chance to introduce it to his students. Soon enough, his students tried the symbols in their respective healing techniques. The eight symbols were indeed very useful. They are brimming with powerful energy that can greatly help in healing other people, or be used for improving one's self.
Karuna Reiki is regarded to be more powerful that Usui Reiki. As such, only a Reiki master is allowed to train in it. Karuna Reiki is deemed much stronger and can heal more deeply than Usui Reiki. However, Rand says that Karuna Reiki is never created to serve as a substitute for Usui Reiki. Instead, it is an additional technique that every Reiki Master can become an expert on.
Karuna Reiki is an evolution of Usui Reiki. With the stronger vibrations brought about by the new symbols used in it, the practice can generate a more superior healing power for Reiki practitioners and masters who are very dedicated to their craft. Usui and Karuna Reiki can even be used together for more effective healing results.
Karuna Reiki can be learned by every Reiki Master, regardless of his lineage. For as long as he is a certified Usui Reiki Master, he is welcome in the Karuna Reiki attunement training.
Aside from the regular Reiki techniques, Karuna Reiki also uses toning and chanting to channel energy from within, which is used to heal, improve, and develop yourself as well as those around you.