Modern genetic and molecular technologies provide a number of tools that can be utilized for the development of staple foods with a higher iron and zinc content and improved bioavailability of these minerals. This article summarizes current strategies aimed at increasing the iron-sequestering capacity of the endosperm and improving mineral bioavailability via in planta synthesis of microbial phytases. A case study is presented for wheat, and future strategies are discussed addressing the importance of phytase thermostability.