AbstractThe issues of size consistency and charge consistency in advanced Green's function theories of ionization or electron attachment spectra are thoroughly discussed by adapting the so‐called third‐order algebraic diagrammatic construction scheme [ADC(3)] to the formalism of crystalline orbitals for an extended periodic system. A comparison is made with a number of lower‐order one‐particle Green's function (or one‐electron propagator) schemes, derived using the general algebraic approach in superoperators and binary products. In the canonical picture, one of the implications of size consistency in the dissociation and thermodynamic limits is that a balance must prevail between the number of satellites and the strength of configuration interactions between the main (1h, 1p) and secondary (shake‐up or shake‐on) states in the cation or anion. Charge consistency, or the preservation of the exact particle number upon correlation corrections to the Hartree–Fock ground‐state one‐electron density, is a necessary condition for the correct, i.e., size‐intensive, scaling of static self‐energies and, thus, ionization energies in large inhomogeneous systems. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem 93: 191–211, 2003