"Materials with strong electronic Coulomb correlations present unique electronic properties such as exotic magnetism, charge or orbital order, or unconventional optical or transport properties, including superconductivity, thermoelectricity or metal-insulator transitions. The concerted behavior of the electrons in these ``correlated materials"" moreover leads to an extreme sensitivity to external stimuli such as changes in temperature, pressure, or external fields. This tuneability of even fundamental properties is both a harbinger for technological applications and a challenge to currently available theoretical methods: Indeed, these properties are the result of strong electron-electron interactions and subtle quantum correlations, and cannot be understood without a proper description of excited states.The aim of the present project is to elaborate, implement and test new approaches to investigate the spectral and optical properties of correlated materials ``from first principles"", that is, without adjustable parameters. I will build on the success of state-of-the-art dynamical mean field-based electronic structure techniques, but aim at developing them into truly first-principles methods, where a full treatment of the long-range Coulomb interactions replaces the current practice of purely local Hubbard interaction parameters. My target materials are among the most interesting for modern technologies, such as transition metal oxides (with potential applications ranging from oxide electronics to battery materials) and rare earth compounds used as environmentally-responsible pigments. Establishing first-principles techniques with truly predictive power for these classes of materials will bring us closer to the final goal of tailoring correlated materials with preassigned properties."