The volume of literature on the subject of mass spectrometry continues to increase and is indicative of the usefulness of the technique in determining various parameters of chemical and physical significance. This review is intended to cover those articles appearing in the literature from January 1960 to November 1961. Momigny (357) reviews the subject in relation to the physical chemistry of molecules and Wagner (498) reviews it with respect to hydrocarbon reactions. The annual Japanese review appears by Tsuchiya, Hashizume, and Someno (486).