Solution-based routes have been widely applied in the synthesis of nanostructures.It is desirable to choose or design precursors,ligands,and solvent molecules at the molecular level to allow the synthesis of lowdimensional nanocrystals with various shapes and sizes.The increasing requirements for the integration of the properties of nanocrystals have produced a high demand for the rational design and fine control of complex structures,in terms of both the composition and the structure.To meet this demand,researchers have developed new synthetic strategies to produce more complex and more functional nanocrystals.Typical procedures involve systematic engineering,which focuses on the whole synthetic procedure,instead of just the molecular details.This review focuses mainly on the work of Yadong Li’s group over the last decade. Solution-based routes have been widely applied in the synthesis of nanostructures. It is desirable to choose or design precursors, ligands, and solvent molecules at the molecular level to allow the synthesis of low dimensional nanocrystals with various shapes and sizes. Increasing rules for the integration of the properties of nanocrystals have produced a high demand for the rational design and fine control of complex structures, in terms of both the composition and the structure. To meet this demand, researchers have developed new synthetic strategies to produce more complex and more functional nanocrystals.Typical procedures involving systematic engineering, which focuses on the whole synthetic procedure, instead of just the molecular details. This review focuses primarily on the work of Yadong Li’s group over the last decade.