Yahoo Peony Group
Peony List deals with all growing aspects of herbaceous and tree peonies, some of the most popular of garden flowers in the world.
American Peony Society
This website is intended to be informative and educational on a wide range of peony topics, everything from backyard planting to the use of peonies as a study-plant.
Swiss Peony Website
Extensive website "from Peony friends for Peony friends" with listings of peoniy varieties, nurseries and more.
The German Peony Society
The Peony-group of the Perennial Society is an non-profit group of amateur collectors, hobby gardeners, peony breeders and nursery men in Germany and the surrounding countries.