A charm is a Animism or Common Magic Foci that contains a lesser Spirit.

If the possessor of the charm has not Concentrated their magic, a charm may only be used as a passive augment to an active skill. Concentrating allows the character to use Common Magic Charms as Active skills, but Tradition Charms can still only be used as passive augments.

However (and I may be reading this wrong) Tradition Charm augments are assumed to ALWAYS BE ON -- unlike a Common Magic charm, they don't have to be specifically activated as an augment (which takes time).

Within an Animist Tradition, Charms are lesser Foci to Fetishes.

I may be wrong, too, but I thought that all charms were always on, even the common magic ones. The downside to charms is that, as foci, they can be taken away from somebody.

Also, it might do good to note that charms are created by practitioners in the same way that fetishes are, essentially. That is, the practitioner "binds" the spirit in question to the object by convincing it that he's friendly, essentially, using the appropriate "worship" ability of the practice to which the spirit in question pertains.

Mike