The dried roots and rhizomes of ginseng (P. ginseng C. A. Meyer) contain many physiologically important constituents. These include ginseng saponins, ginseng oils and phytosterol, carbohydrates and sugars, organic acids, nitrogenous substances, amino acids and peptides, vitamins and minerals, and certain enzymes that have been isolated and characterized. Among these, ginseng saponins are proven to be the principal and most active constituents. Chemical research, therefore, has been focused on these saponins--their extraction, purification, identification, isolation of aglycones (genins), and biosynthesis. So far 13 saponins have been isolated and identified and these, which have been called ginsenosides or panaxosides, are triterpenes of dammarane and oleanane structures. Although American, Japanese, San-ch'i, Himalayan, and Siberian ginseng roots contain many saponins similar to those found in ginseng, the overall components in these ginseng species are quite different. The above-ground parts, particularly the leaves, of these ginseng plants contain many of the saponins normally present in the roots. The search for economical sources of ginseng saponins from nature and even chemical synthesis may likely become the active ginseng research of the future. Continued, meticulous studies are undoubtedly needed to develop these natural panacea into useful, efficacious modern remedies.