An ND is a doctor of naturopathy or a naturopathic physician. Only a handful of naturopaths are NDs. To obtain an ND (which allows the practitioner to be licensed in states that license NDs), a person must attend a four-year, postgraduate medical program, following three to four years of undergraduate education. These providers are trained to be primary care doctors who use naturopathy as their first course of intervention, though they can often prescribe prescription medicines as well.