Recently, heterogeneous structure is found to produce unprecedented strength and ductility that are considered impossible from our textbook knowledge and materials history. In addition, it also exhibits other unusual mechanical behaviors such as very high strain hardening rate. It is suggested that mechanical incompatibility between heterogeneous domains is primarily responsible for the observed phenomenon. This represents a new paradigm for designing strong and tough structural materials. Heterogeneous materials have recently attracted extensive attention in the academic community and are emerging as a hot research field. Importantly, heterogeneous materials can be produced by currently available industrial facilities at low cost, and has the potential to revolutionize the manufacturing industry by providing strong materials for energy efficient transportation vehicles and other applications. In this talk we will present and discuss the perspective, prospects, and problems of heterogeneous materials.