* California School of Herbal Studies: The California School of Herbal Studies is a private, non-profit school in Santa Cruz, California, that offers a two-year Certificate in Herbal Studies program. The program is accredited by the American Herbalists Guild (AHG).
* David Winston's Center for Herbal Studies: David Winston's Center for Herbal Studies is a private, non-profit school in Washington, New Jersey, that offers a two-year Certificate in Herbal Studies program. The program is accredited by the American Herbalists Guild (AHG).
* Herbal Academy of New England: The Herbal Academy of New England is a private, non-profit school in Greenfield, Massachusetts, that offers a two-year Certificate in Herbal Studies program. The program is accredited by the American Herbalists Guild (AHG).
* Susun Weed's School of Herbal Medicine: Susun Weed's School of Herbal Medicine is a private, non-profit school in Woodstock, New York, that offers a two-year Certificate in Herbal Studies program. The program is accredited by the American Herbalists Guild (AHG).