A Practice Note providing an overview of the Food and Drug Administration's (FDA) regulation of dietary supplements under the Federal Food, Drug, and Cosmetic Act (FDCA), as amended by the Dietary Supplement Health and Education Act of 1994 (DSHEA). This Note covers the definition of "dietary supplement," new dietary ingredients (NDIs) and old dietary ingredients (ODIs), dietary supplement safety, statements of nutritional support ("structure/function" claims), labeling requirements, serious adverse event reporting, current good manufacturing practices (CGMPs), and potential consequences for noncompliance with FDA requirements.