BSTRACTHeterostructures with large microstructural heterogeneities have been introduced in structural materials for superior strength-ductility combinations

but their effects on functional properties remain little explored. Here I highlight the enormous potential of heterostructures to resolve conflicting properties in functional materials. The challenges

strategies and prospects of heterostructured functional materials are discussed. Rational design of heterostructures will open up new opportunities for creating functional materials with unprecedented performance or new functionalities. This Perspective aims to draw the attention of scientific community to the emerging heterostructured functional materials and to trigger intense fundamental and applied researches on this topic.