This paper presents procedures for computing stresses in floating-head and fixed-tubesheet heat exchangers. It does not cover U-tube exchangers. It was prepared in connection with the activities of the Special Working Group on Heat Transfer Equipment, Section VIII, of the ASME Boiler and Pressure Vessel Code Committee, for their use and consideration in the drafting of code rules for these items. The mathematical procedures are closely associated with the publications of K. A. Gardner and K. A. G. Miller [1–3].