Advanced electronic structures methods for many-electron molecular systems. This course will cover the fundamentals of quantum many-body theory applied to the electronic structure of molecules from a quantum chemist's point of view. Topics discussed are: solution methods to 1-body problems (hydrogen atom and harmonic oscillator), approximation to the wave function (perturbation theory and the variational principle), 1st and 2nd quantization, Configuration Interaction, single-reference approximations (Hartree-Fock & Density Functional Theory), contemporary methods for strong electron correlation (Coupled Cluster, DMRG, ...).