The term "incompatibilities" describes a wide range of chemical reactions that produce undesirable results in noncontrolled situations: the generation of toxic gases, fire, explosions, corrosive activity, polymerization, ruptured containers, creation of more dangerous compounds, and the like. A portable and easy-to-use reference on reactive substances commonly found in commerce compiles hard-to-find data on over 11,000 chemical compounds, providing chemists, technicians, and engineers a thorough, resource to use during experimental preparation and in the event of an emergency.