The Gesneriad Reference Web: This is the site for a fantastic number of photographs of gesneriad plants.
The Gesneriad Society, formerly the American Gloxinia and Gesneriad Society, is the registration authority for Gesneriads other than African violets and the website has a wealth of information and photographs.
The World Checklist of Gesneriaceae: The Smithsonian Institution's National Museum of Natural History , this is the ultimate resource to check the standing of botanical names of species in the gesneriad family.
Brazilian Plants: This website of Mauro Peixoto has information and photographs of Brazilian gesneriads such as Nematanthus and Sinningia.
Vancouver African Violet and Gesneriad Society: one of several Canadian sites.
Some good sites for specific genera include:
Streptocarpus: Dibleys Nurseries in Wales; UK) & British Streptocarpus Society
Sinningias: Sinningia Friends : has photographs and growing information on many species.
