Bach's is made of flower essences - and a high percentage of alcohol. It is 240 parts brandy ~~looking at the bottle right now~~ to one part flower essences. It is more of a
herbal remedy than it is a
homeopathic one.
Does it work? I don't think for severe panic attacks it is very effective, but I know a lot of people who buy it from the shop who swear by its calming and soothing effects on their system when they are stressed. I do carry my bottle around with me at work, I find it works on a certain level...but, I do suffer from severe anxiety...and it just isn't going to touch those greater symptoms (like when I start to hyperventilate, etc.) There are stronger natural things (both herbal and homeopathic) for the worse symptoms of stress.
Homeopathy works on the principal that "like fixes like". It uses very small doses of substances to trigger the body's natural healing mechanisms. Herbology (or Phytotherapy), on the other hand, is more traditionally
medicinal.
Gotta love homeopathy, though. Where else could I sell arsenic and belladonna (deadly nightshade) - as a remedy - and get away with it?

When homeopathic remedies are regulated to the point where all dosage directions, counter-indications, etc. are clear and consistent -- then I'll try them.
There are NO contraindications with homeopathic remedies, UNLIKE herbal remedies. Therein lies one of the differences. For the person who wants to try "natural" therapies, I recommend always going to the professionally trained for advice, and preferably, for serious conditions, to go to a practitioner of natural medicine: i.e. a Naturopath, Homeopath, Phytotherapist, etc.