A comparison between compositionally stepped and alternating step‐graded structures used in the production of a relaxation buffer layer is carried out by means of transmission electron microscopy. The latter shows higher efficiency in relieving the strain. A simple balance force model permits us to understand the reason for a higher generation of threading dislocations observed in the alternating step‐graded structures. The presented results can be applied as new design rules for buffer fabrication that contrast in some key points with previous published rules as, for example, the ‘‘zero‐net‐strain’’ precept [D. Dunstan, P. Kidd, P. F. Fewster, N. L. Andrew, L. Gonza´lez, Y. Gonza´lez, A. Sacedo´n, and F. Gonza´lez‐Sanz, Appl. Phys. Lett.65, 845 (1994)]. ©1995 American Institute of Physics.