Gastrodia elata (Tianma) is the most important species of orchid used in traditional medicine. It is the principal herb used for the prevention and treatment of strokes and for neurological disorders which include Parkinsonism and dementia. Gastrodia elata is present in many patent Chinese herbal remedies. More than 50 compounds have been isolated from this orchid. Their neuro-protective and other effects, and those of crude Gastrodia elata extracts are extensively discussed in this chapter. Chinese scientists have also discovered a way to cultivate the orchid. Other orchid genera described in this chapter are Galeola, Gastrochilus, Geodorum, Goodyera, Grammatophyllum and Gymadenia. Examples are provided on how these orchids are used in Traditional Chinese Medicine and other traditions.