Anyone can learn Reiki, and indeed anyone can channel healing energy with or without the reiki attunements. Ooops I might get into trouble for saying that..but I've had a lot of experience working in groups, and attuned and not-attuned people can channel just the same. The difference with Reiki is it comes through a long stronger in the beginning (ie before you've had a lot of experience), although without the attunement, people who practice regularly can achieve similar results. Reiki is more systematic too in the way it is applied.
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Nope, I totally agree MD - one of my friends was already healing, for her it was an added extra. I think in some instances the Reiki attunements 'open you up' so to speak, some people may have the belief that they need them (and thus, do) but I definitely think you can channel with or without them.

As for being systematic, I understand what you are saying, I have never been taught systematically, my teachers were very big on being intuitive - I sometimes wonder if I should look into a more systematic approach, it would be interesting to see what it feels like ITMS.

Boomba I would love to