The first important patents on synthetic resins were granted about 25 years ago. These patents covered phenolic resins probably intended for use as substitutes for certain natural resins. It was soon found that these synthetics offered possibilities of application vastly greater than the natural materials. At first progress in their application was slow as is usually the case with new products. During the World War the shortage of phenol promoted interest in the use of the other tar acids as raw materials for synthetic resins and intensive research developed resins from the cresols and higher boiling tar acids. These resins possessed properties sufficiently different from those made from phenol to establish them permanently. In the meantime research on other types of resins was carried on in the United States and in Europe. The tar-acid resins for molding were the only commercially important ones on the market until about 1929. About that time, however, new commercial products began to appear rapidly. Cast phenolic resins became available as material for novelties of unusual brilliancy and beauty, the urea resins to meet the requirements for light colored thermosetting resins in molded articles, and the alkyd resins for use in new surface coatings which replaced conventional paint materials. Later there followed a number of thermoplastic materials offering new and unusual properties. Vinyl resins found application in molded products and in safety glass. The acrylate resins became the nearest approach to organic glass yet developed. The polystyrene resins, long in the research stage, made their commercial appearance in 1937. Resins from petroleum, from furfural, from adipic acid, and from aniline are on the market. Many others are under investigation and some of them will undoubtedly become important. The versatility of synthetic resins is most unusual. In various uses they have successfully displaced glass, wood, metal, hard rubber, bone, glue, cellulose plastics, protein plastics, and conventional paint materials. They compete with glass in shades and reflectors and offer properties which will increase their use for this purpose. Cases for scales, radios, and clocks, formerly of wood and metal, are now made of these synthetic resins. Scope and purpose.