In the course of a fundamental study of metal cutting it was found that a cutting fluid encounters a rather unusual combination of conditions at the point of a cutting tool. The fluid is subjected to high local pressures of the order of the hardness of the metal cut, high local temperatures limited only by the melting point of the work material, and nascent highly stressed metal surfaces. This combination of conditions will, in general, promote a chemical reaction. The organic chemist uses reactions between metals and organic reagents in chemical synthesis, many of these so-called organometallic reactions being difficult to initiate and control. In this paper it is shown how the metal-cutting process may be employed in the preparation of organometallic compounds. The metal involved in the preparation is cut in the presence of the other reactants, thus utilizing the high-temperature, high-pressure, and highly stressed nascent surface produced at the point of cutting to start the reaction. This process has been called mechanical activation. This new chemical technique promises to give many extremely versatile organometallic reactions a commercial significance which they have heretofore lacked because their application was limited to batch rather than continuous processes by the inflammability and toxicity of the reactants, and the difficulty of starting and controlling the reaction.