Hybrid perovskite electronic band structure from atomic orbitals, spin-orbit coupling, and exciton molecular screening. This paper reviews how solid-state physics concepts can be adapted to this “new” class of semiconductors and shows that it provides valuable tools when combined with DFT simulations of the optoelectronic properties. The pseudocubic perovskite structure plays a central role in this approach, allowing us to define reference Bloch states and empirical Hamiltonians close to the electronic band gap. Lattice distortions including loss of inversion symmetry as well as spin-orbit coupling have a strong impact on the electronic band structure, in particular, regarding band folding, degeneracy, effective masses, Rashba–Dresselhaus effect, and optical absorption. Many-body interactions such as Auger effects are discussed starting with excitonic interactions, where screening and dielectric confinements are of utmost importance for the optical properties at room temperature. See page 10161 [doi: 10.1021/acs.jpcc.5b00695].