Scoliosis can only be treated with a back brace if caught early while the person is still a youth, or with surgery. I have seen both these treatments work with amazing results.  Exercises will help to better support the body, but unfortunately will not alter the spine since scoliosis is a congenital condition.

If the condition is mild, core work will help build up the muscles of the back and abdomen so the back has better support. For those with milder conditions, yoga or even Pilates help by strengthening the core thus providing more support for the spine. Core exercises performed in the upright or standing position prevent pressure on the spine.

Another strategy is to work arms and legs. Everybody benefits from leg and arm work.  Posterior deltoid work will help with any kyphosic tendencies. Water exercises are great because the water is supportive and provides cushioning while still being weight bearing. Tai Chi is a martial art form that may help your clients with flexibility and balance without causing jarring or being too challenging.