Abstract: The theoretical understanding of the electronic and optical properties of strained semiconductor nanostructures, such as quantum dots, has been quite successful, in spite of the uncertainties in the composition and geometry of the structures, and the material properties. As experimentalists have developed more exotic structures, such as nanowire quantum dots and quantum posts, additional complications arise. For example, nanowires typically have a different crystal structure from the bulk materials, and large quantum posts can confine 5 or 6 electrons. I will discuss the progress in understanding of these structures, including calculations of strain and material segregation effects, electron-electron interactions, and exciton lifetimes.