The volume contains the lectures delivered at the XII Training Course in the Physics of Strongly Correlated Systems, held in Vietri sul Mare (Salerno) Italy, in October 2007. The focus of the meeting was to promote the formation of young scientists by means of training through research. These features are reflected in the book: the lectures are up-to-date monographies of relevant subjects in the field of Condensed Matter Physics. Contributions include: Quantum Magnetism (Independent spins and Weiss meanfield theory; Finite Heisenberg clusters; Linear spin-wave theory; Classical and quantum Monte Carlo; Entanglement in quantum spin systems); Nanomagnets and Entanglement (The Dynamical Mean Field and Cluster Approximations; Quantum Monte Carlo Algorithms for the Quantum Cluster Problem; Analytic Continuation of Quantum Monte Carlo Data); The Dynamical Cluster Approximation with Quantum Monte Carlo Cluster Solvers (Fermi liquids; Fermi-liquid instabilities at quantum phase transitions: theory; Fermi-liquid instabilities at quantum phase transitions: experiment; Metal-insulator transition in heavily doped semiconductors); Quantum phase transitions; Correlated thermoelectric (Phenomenological equations; Physical interpretation; Solution of transport equations; Linear response theory; Current operators; Mahan-Jonson theorem; Microscopic solution for transport coefficients).