Water soluble gums of plant origin represent an enormous quantity of industrial material supplied by plant growing areas in most parts of the world (Whistler, 1973). Gums come from a variety of plants and are separated by a variety of methods. Their use began before recorded history, starting in all probability as thickeners for foods in gruels, long before their next major use as sizing for paper and textiles. Today, usage of natural water-soluble gums is growing at the rate of 10%/yr. But the hard hand of economics is changing the types of gums that are used. Slowly, but irresistibly, labor cost escalation even in remote areas and the quality control needed for relatively pure and constant quality raw material cause some plant sources to be eliminated and others, perhaps more amenable to cultivation, to appear as new sources. Water-soluble gums are seldom used alone in applications but, almost always, are mixed with other materials. Their principal role is to control physical properties. They are excellent suspending agents, dispersants, stabilizing agents, emulsifiers and gel-forming agents. On occasion, they are used as coagulants, binders, lubricants or film formers. They are all carbohydrate polymers composed of sugar units glycosidically condensed to form large molecules. As a consequence they are, for the most part, of high molecular weight, some linear and some branched, even extensively branched or bush shaped. As might be expected, a more or less extended linear polymer will sweep out a larger space as it gyrates than will a highly branched, bush-shaped polymer of the same molecular weight. Hence, linear soluble polysaccharides will have very high viscosities at low concentrations. Branched polysaccharides may have high viscosities also if their molecular weight, degree of polymerization, is high. In this short discussion, I wish to describe a few plant gums and present some information on several that are important or may become important in the United States.