How does it work?
Just as we each have a digestive system, a nervous system or a cardio-vascular system, we have an energy system too.  It 's not such a peculiar idea; we've all had times when our energy is low and we haven't been able to enjoy the things that normally give us joy - let alone do all the tasks we have in front of us in a day.  In just the same way, we've all had times when we've been full of life, raring to go, feeling that we can tackle anything.  It makes sense that when our energy is low there won't be enough to keep us going and at the same time to heal whatever injury, sickness or disease we're suffering from.  And if there's energy to spare then some of it can go towards restoring health.
Somehow or other, the ancient Chinese discovered that there were places on the body which, if stimulated, would alter its energy, and that in turn would have have highly specific and very profound effects on tissue and the organs  The old texts contain predictions of the kind 'if you insert a needle here then this is the change you will see in the rhythm of the heart (or the digestive system, or the menstrual cycle)' - and those predictions still come true today.

What happens in a treatment?
Normally , the first twenty minutes or so are taken up with talking.  Each treatment is individual to you and to your complaint, so I'll need to understand how you are in order to plan the best treatment for you.  Then I will feel the pulses on each wrist and I'll look at your tongue as these give vital information about the state of your energy system.

Then I'll choose which points to use.  Most often they are on the arm from the elbow down and on the leg from the knee down.  The needles may be inserted only for a second or two or they can stay in for up to twenty minutes.  Either way (apart from a few specific points which really do hurt, and I'll always ask your permission before using them) the sensation is momentary and not like pain; more a kind of ache or a fizz.

Do you have to believe in it for it to work?
Absolutely not.  I have had plenty of patients who have been sceptical or  downright dubious and it hasn't made any difference at all.  In any case lots of vets use it and their patients, presumably, don't believe in this system of medicine.

What conditions is it good for?
My own experience as a patient was that after having acupuncture in my early forties my lifelong asthma went away, never to return.  As a practitioner, like countless thousands of others in the past two thousand years or so, I have treated a very wide range of conditions succesfully - menstrual problems, irritable bowel, migraines, infertility, back pain, poor circulation, insomnia, arrythmia and so on. 
However, the law in the UK is that I cannnot say that acupuncture treats these conditions because there have been no double blind trials which prove that it works.  In my view, that is because those trials were designed to test the efficacy of drugs, which are manufactured on the basis that each disease works in the same way in every person.  Acupuncture, on the other hand, holds that each disease is different in each person - your asthma is not quite the same as mine - and hence each treatment is individually crafted.  And what that means is that the trials used to test the efficacy of drugs simply don't work to test acupuncture treatments.