A simplified design procedure is presented to determine tubesheet thickness in U-tube, floating-head, and fixed-tubesheet shell-and-tube exchangers. The procedure is based on classical plate-and-shell theory and permits a design code-oriented manual solution procedure. The configuration analyzed includes an unperforated rim, three different tubesheet head-shell-joint configurations, and arbitrary material properties for each component. Thermal loading due to differential radial expansion and the effect of local pressures acting on the head and shell walls are included.