Abstract A set of design principles for stacks of epitaxial layers with different lattice parameters is described. The thickness and composition of each layer is determined using a novel design method which aims to reduce the likelihood of edge dislocation formation within the epilayer by ensuring that the 60° dislocations at each interface are separated to such an extent that dislocation glide along {111} planes to form an edge dislocation necessitates the traversing of another interface. This implies that the two 60° dislocations which could glide to form an edge dislocation would have to interact with the dislocation array present at the InxGa1‒xAs/InyGa1‒yAs interfaces. Such interactions will reduce the number of edge dislocations created in the structure. Edge dislocation suppression is important since these dislocations are sessile and can block gliding threading dislocations, trapping them within the layer and reducing the extent of strain relief and thus the quality of possible devises. Stacks of ...